This course develops students' understanding of the basic concepts of physics. Students will study the laws of dynamics and explore different kinds of forces, the quantification and forms of energy (mechanical, sound, light, thermal, and electrical), and the way energy is transformed and transmitted. They will develop scientific-inquiry skills as they verify accepted laws and solve both assigned problems and those emerging from their investigations. Students will also analyze the interrelationships between physics and technology, and consider the impact of technological applications of physics on society and the environment. Prerequisite: Grade 10 Science SNC2D (Academic)

Scalar measurements have only have a magnitude (no direction). Vectors have both magnitude and direction.

For example*45 meters West* is a vector quantity.

For example

Scalars: Distance, Time, Mass, Speed...

Scalar quantities do not have direction, and consist only of a magnitude.

Scalar quantities do not have direction, and consist only of a magnitude.

Vector quantities have *both* direction and magnitude.

The three vectors are velocity, displacement, position, and acceleration. (Force is another vector, not shown here).

The three vectors are velocity, displacement, position, and acceleration. (Force is another vector, not shown here).

Event | Distance (km) | Time (min) |

Swimming | 3.86 | 76 |

Cycling | 180 | 385 |

Running | 42.2 | 294 |

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

Hint Unavailable

Convert kilometers to meters, and minutes to seconds:
Total distance divided by total time:

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

Convert speed units into m/s: 216 km/hr ÷ 3.6 = 60 m/s

The circumference is the distance: multiply by 10 to get the total distance.

The circumference is the distance: multiply by 10 to get the total distance.

For example if you were to walk most of the distance to some place and sprint the last 10 meters, then the average speed would likely be much lower than the instant you were sprinting the fastest speed.

Distance is the total length (7,180m + 7,180m), while __displacement is the change in position__ (+7,180m - 7,180m). Since the runner returns to the starting position, the change in position is zero.

Average Velocity is a __change in position__ divided by time, and depends on the total displacement, rather than the distance. If the change in position equals zero, then the average velocity also equals zero.

This is non-uniform motion because there is acceleration.

Remember that acceleration is non-uniform motion, so the soccer ball has non-uniform motion.

Acceleration can be zero at rest or in constant motion. For example if a jogger runs at a constant 9 km/hr, then acceleration = 0.

Since the motion is defined as being in the positive direction, then the velocity is positive.

"Speeding up" in the positive direction indicates that there is positive acceleration.

(If the object was "slowing down" in the positive direction, then the acceleration would be negative).

"Speeding up" in the positive direction indicates that there is positive acceleration.

(If the object was "slowing down" in the positive direction, then the acceleration would be negative).

Hint
Clear
Info

Incorrect Attempts:

CHECK

s

Hint Unavailable

The initial velocity is +100 m/s, the acceleration is -4.0 m/s^{2}, and the final velocity is 0 m/s. Find time:

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

The initial velocity is +100 m/s, the acceleration is -4.0 m/s^{2}, final velocity is 0 m/s, and time is 25 s. Find distance:

Mass does not matter, the both the bowling and golf balls will hit the ground at the __same time__. None of the kinematics equations have mass in them. They will fall with the same time have the same final velocity on impact at the ground.

Gravity is the acceleration causing the motion of the two balls, and assuming this is on Earth, then it is the same for both balls.

Gravity is the acceleration causing the motion of the two balls, and assuming this is on Earth, then it is the same for both balls.

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

Use 12.2 m/s as your initial velocity and the final velocity = 0 m/s

This distance calculated will be one-half of the maximum height.

__Givens:__

v_{1} = 12.2 m/s

v_{2} = 0 m/s

a = -9.8 m/s^{2}

calculate d:

Since this is half the maximum height, then the maximum height is__3.1m__

This distance calculated will be one-half of the maximum height.

v

v

a = -9.8 m/s

calculate d:

Since this is half the maximum height, then the maximum height is

Hint
Clear
Info

Incorrect Attempts:

CHECK

s

Hint Unavailable

Use the maximum height of 3.1 m

__Givens:__

v_{2} = 0 m/s

a = -9.8 m/s^{2}

d = 3.1m

Find time (t)

The total time is 0.8 seconds.

v

a = -9.8 m/s

d = 3.1m

Find time (t)

The total time is 0.8 seconds.

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

Hint Unavailable

v

a = -9.8 m/s

t = 0.8 s

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s [S]

Hint Unavailable

v

a = 5 m/s

t = 5.0 s

Find v

Hint
Clear
Info

Incorrect Attempts:

CHECK

s

Hint Unavailable

v

v

a = -10 m/s

Find t

Position is a vector quantity.

Displacement is a vector quantity.

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

Hint Unavailable

Velocity is a vector quantity that involves displacement.

Velocity is zero where the y-axis indicates 0 m/s, which is located at 16 seconds.

• The **slope on a velocity-time graph represents the acceleration**.

• The flat line in phase I indicates a slope of zero, so the acceleration is zero.

• Phase II has a negative slope, which is negative acceleration.

• Phase III has a positive slope, which is positive acceleration.

• Phase IV is a curve, which is a non-uniform acceleration as it constantly changes and would have different instantaneous accelerations along the curve.

• The flat line in phase I indicates a slope of zero, so the acceleration is zero.

• Phase II has a negative slope, which is negative acceleration.

• Phase III has a positive slope, which is positive acceleration.

• Phase IV is a curve, which is a non-uniform acceleration as it constantly changes and would have different instantaneous accelerations along the curve.

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s^{2}

Hint Unavailable

Average acceleration is just from the first point at 0s to the last point at 12s.

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

Hint Unavailable

Change in velocity = **area** under acceleration time function.

Drawing a sketch of the compass heading on a N-E-S-W system shows that the two headings overlap and are the *same*: [S 70˚ E] and [E 20˚ S].

Break into components...

Hint
Clear
Info

Incorrect Attempts:

CHECK

km/hr [N 53˚ E]

Hint Unavailable

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s [West]

Hint Unavailable

Here I choose to define West as positive, and East as negative.

v =

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s [N 31.2˚ E]

Hint Unavailable

Do a sketch and determine that the obtuse angle = 23˚ + 90˚ + (90˚ - 43˚) = 160˚

Use the cosine law to solve for the resultant, which is the longest side length in the triangle in your sketch.

__Givens:__

b = 3.6 m/s

c = 2.3 m/s

A = 160˚

Solve for the direction using sin law (given side-side-angle)... 43˚ - 11.8˚ = 31.2˚

Therefore the velocity = 6 m/s [N 31.2˚ E]

Use the cosine law to solve for the resultant, which is the longest side length in the triangle in your sketch.

b = 3.6 m/s

c = 2.3 m/s

A = 160˚

Solve for the direction using sin law (given side-side-angle)... 43˚ - 11.8˚ = 31.2˚

Therefore the velocity = 6 m/s [N 31.2˚ E]

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

v

v

t = 5.0 s

Find d

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

Hint Unavailable

d = 0.5 km = 500m

t = 1:40 min = 100s

v

Find v

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s^{2}

Hint Unavailable

v

v

t = 10 s

Find

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

Hint Unavailable

a = 5 m/s

t = 15 s

v

Find v

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s [E]

Hint Unavailable

= 3 m/s

t = 23s

d = 839.5m

Find

Hint
Clear
Info

Incorrect Attempts:

CHECK

s

Hint Unavailable

d = 73.5m [W]

a = 3 m/s

= 0

Find t

Hint
Clear
Info

Incorrect Attempts:

CHECK

s

Hint Unavailable

d = 85.0m

a = 6 m/s

= 2 m/s

Find t

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

Hint Unavailable

= 5 m/s

d = 52m

t = 4s

Find

Hint
Clear
Info

Incorrect Attempts:

CHECK

s

Hint Unavailable

= 3 m/s

d = 37.5m

= 0 m/s

Find t

Hint
Clear
Info

Incorrect Attempts:

CHECK

m [S]

Hint Unavailable

= 4 m/s

= 15 m/s [S]

= 23 m/s [S]

Find

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

Hint Unavailable

= 3.2\ m/s

d = 85m

= 34.2\ m/s

Find

Ignoring air resistance, the acceleration of falling objects (any masses) is the same because the acceleration (gravity) is the same, 9.81 m/s^{2} [Down] and the initial velocities are the same.

As you can see in the equation below, the final velocities of the different masses would be the same (because initial velocity, acceleration, and displacement are the same) so the masses would hit the ground at the same time.

As you can see in the equation below, the final velocities of the different masses would be the same (because initial velocity, acceleration, and displacement are the same) so the masses would hit the ground at the same time.

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s^{2} [↓]

Hint Unavailable

In this case, *g* does not represent grams, rather it represents the unit of gravity, -9.81 m/s^{2}.

So would be

So would be

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

The vertical component of the motion of the baseball has the same time as the whole projectile motion. So we will solve for height based on the purely vertical component of the motion.

__Givens:__

v_{1 y} = 0 m/s

t = 4 s

a = -9.81 m/s^{2}

Find height,*h*

v

t = 4 s

a = -9.81 m/s

Find height,

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

Hint Unavailable

In the horizontal (x) component direction--motion is uniform, or constant velocity:

__Givens:__

d_{x} = 25 m

t = 4 s

Find v_{x}

d

t = 4 s

Find v

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

Hint Unavailable

In the vertical (y) component direction:

(Note that the time is the same in the*x* and *y* components)
__Givens:__

v_{1 y} = 0 m/s

t = 4 s

a = -9.81 m/s^{2}

Find v_{2 y}

(Note that the time is the same in the

v

t = 4 s

a = -9.81 m/s

Find v

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

Hint Unavailable

This question uses values calculated previously (final velocity components in the 'x' and 'y' direction). You must calculate these (not shown here) if you haven't already, hence the significance of this question. Use vector addition of the *x* and *y* velocities found previously. Use pythagorean theorem:

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s^{2}

Hint Unavailable

v

v

t = 6.0 s

Find a

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

Hint Unavailable

v

a = 3.3 m/s

t = 4.0 s

v

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

v

a = 3.3 m/s

t = 4.0 s

d = ?

Kilogram

Weight = Mass × Gravity

Commonly known as the *law of inertia*. Newton's first law in his own words, translated from Latin to English: "Law I: Every body persists in its state of being at rest or of moving uniformly straight forward, except insofar as it is compelled to change its state by force impressed."

Newton's third law. For every action, there is an equal and opposite reaction

A body will continue in motion unless acted upon by a net force, the seatbelt providing the force holding the occupant back at the same motion as the car. In other words, the person's body would continue moving forward into harm without the force of the seatbelt holding it back.

Newton's third law. The collision involves two different masses colliding in opposite directions. Even though the masses are different, the objects will experience *equal and opposite* forces.

Constant motion (or zero motion) involves a balance of forces. For the skiier their normal force would balance with the force due to gravity (if we neglect friction).

Newton's first law: an object stays at rest or in constant motion unless acted upon by a *net* force. Terminal velocity occurs when there is *no net force* because the force due to gravity is equal and opposite to the force of friction of the air (Newton's third law).

Hint
Clear
Info

Incorrect Attempts:

CHECK

N [West]

Hint Unavailable

The forces are opposite in direction, but are not equal magnitudes. Therefore there is a net force of -1 Newton West.

Hint
Clear
Info

Incorrect Attempts:

CHECK

N [S 61.1˚ W]

Hint Unavailable

Vector addition of the two forces, using pythagorean theorem since the two forces are perpendicular... = 6624 N

F = m • a

Increasing acceleration (with constant mass) increases the force.

Increasing mass (with constant force) decreases the acceleration.

Increasing acceleration (with constant mass) increases the force.

Increasing mass (with constant force) decreases the acceleration.

Hint
Clear
Info

Incorrect Attempts:

CHECK

times higher

Hint Unavailable

Show the force due to gravity (F_{g}) downwards and the force of tension (F_{T}) in the apple stem upwards.

The sled has a normal force (F_{N}) downwards, the rope has a tension force (F_{T}) in the rope due equal to the applied force (not shown). There is also the force due to gravity (F_{g}) downwards on the sled.

Force due to gravity (F_{g}) downwards on the bricks and tension force (F_{T}) up in the crane cable.

Hint
Clear
Info

F_{NET x} = N F_{NET y} = N

Incorrect Attempts:

CHECK

Hint Unavailable

(F_{NET y} = 0 N)

Hint
Clear
Info

F_{NET x} = N F_{NET y} = N

Incorrect Attempts:

CHECK

Hint Unavailable

Hint
Clear
Info

F_{NET x} = N F_{NET y} = N

Incorrect Attempts:

CHECK

Hint Unavailable

Hint
Clear
Info

F_{NET x} = N F_{NET y} = N

Incorrect Attempts:

CHECK

Hint Unavailable

Hint
Clear
Info

F_{NET x} = N F_{NET y} = N

Incorrect Attempts:

CHECK

Hint Unavailable

Hint
Clear
Info

Incorrect Attempts:

CHECK

N

Hint Unavailable

F = ma = ... = 8000 N

Hint
Clear
Info

Incorrect Attempts:

CHECK

N

To lift upward, off the ground, the 'y' component of the force tension opposes the force due to gravity

Think about the two opposite and parallel forces that are opposing,

F =

Hint
Clear
Info

Incorrect Attempts:

CHECK

N

Hint Unavailable

m = 20,000 kg

a

Find F

The equation F_{f} = F_{µ} × F_{N} shows that the units of force cancel (Newton), leaving behind the unit-less coefficient of friction.

t =

Hint
Clear
Info

Incorrect Attempts:

CHECK

s

Hint Unavailable

m = 400 kg

v

F

V

F

Hint
Clear
Info

Incorrect Attempts:

CHECK

N

Hint Unavailable

m = 400 kg

a = 0.5 m/s

F

F =

Hint
Clear
Info

Incorrect Attempts:

CHECK

N

Hint Unavailable

m = 0.10 kg

v

v

t = 0.25 s

Find F Calculate acceleration first: Then calculate net force:

a =

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s^{2} down

Hint Unavailable

m

m

Find a The observed mass on the scale is an indication of the reactive Normal Force (F

a =

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s^{2} up

Hint Unavailable

m = 200 kg

F

Find a

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hint Unavailable

µ_{s} =

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hint Unavailable

m

m

v

a = ±0.37 m/s

Find F

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hint Unavailable

See that __increasing the mass of the bricks__ would increase the acceleration...

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hint Unavailable

True, this is what allows the car to drive forward... force of static friction and direction of car acceleration are in the **same direction**.

The *forces of static and kinetic friction* carry the box forward... same direction.

Hint
Clear
Info

Incorrect Attempts:

CHECK

s

Hint Unavailable

v

v

µ

Find time Force due to friction is in the same direction as the net force on the package - they are equal. First get acceleration with net force equation: Now that you have acceleration, calculate the time with kinematics:

Weight (mg) is constant.

Weight and the coefficient of static friction are constant. The force of friction increases.

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hint Unavailable

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s^{2}

Hint Unavailable

Hint
Clear
Info

Incorrect Attempts:

CHECK

N

Hint Unavailable

True

True, at the Earth's surface, it is approximated as roughly -9.81 m/s^{2}.

True

Make sure to use Newton's Law of Universal Gravitation at altitudes high above the Earth's surface, and not the simplification (F_{g} = mg)

The units of gravitational field strength (g) are ms^{-1} or Nkg^{-1}.

radius

Gravitational constant, G = 6.67 × 10

F_{g} =

Hint
Clear
Info

× 10

Incorrect Attempts:

CHECK

N

Hint Unavailable

Hint
Clear
Info

Incorrect Attempts:

CHECK

times higher

Hint Unavailable

Temperature is not a form of energy, but *heat* is.

Radiation is the only form of energy that can travel through a vacuum (space without matter).

A *scalar* is a magnitude without a direction.

Hint
Clear
Info

Incorrect Attempts:

CHECK

kg

Hint Unavailable

350cm = 3.5m

W =

Hint
Clear
Info

Incorrect Attempts:

CHECK

J

Hint Unavailable

Use __the displacement__ in the same direction as the force. Work is conservative, meaning the magnitude __does not depend on the path taken__.

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

1,000cm = 10m

moon's gravity = 1.6 m/s^{2}

earth's gravity = 9.8 m/s^{2}

Work = (Force) × Distance = (Mass × Gravity) × Distance.

moon's gravity = 1.6 m/s

earth's gravity = 9.8 m/s

Work = (Force) × Distance = (Mass × Gravity) × Distance.

W =

Hint
Clear
Info

Incorrect Attempts:

CHECK

J

Hint Unavailable

While there is a vertical force (F_{g} = mg), there is no displacement parallel to this force.

__The stone does not move, displacement = 0__
Work is the energy applied by an applied force *over a change in position*. Work is zero when the displacement parallel to the force is zero.

- Work due to gravity on a hockey puck sliding with constant velocity across a frictionless surface.
- Work done on an object that experiences no forces.
- Work due to the normal force of a computer resting on the flat surface of a table.

W = F · d

- Work equals zero when the distance direction is not parallel to the force direction. Force of gravity is vertical while the distance travelled is horizontal, or the distance in the same direction is zero, so work is zero.
- Force equals zero, so work equals zero.
- Distance equals zero, so work equals zero.

Mechanical energy is constant the whole way because it is always a sum of gravitational potential and kinetic energies.

Hint
Clear
Info

Height | Gravitational Potential Energy | Kinetic Energy | Total Mechanical Energy |

10.0 m | J | J | 10 J |

5.0 m | J | J | 10 J |

0 m | J | J | 10 J |

Incorrect Attempts:

CHECK

Hint Unavailable

total mechanical energy = gravitational potential energy + kinetic energy

Height | Gravitational Potential Energy | Kinetic Energy | Total Mechanical Energy |

10.0 m | 10 J | 0 J | 10 J |

5.0 m | 5 J | 5 J | 10 J |

0 m | 0 J | 10 J | 10 J |

Hint
Clear
Info

Incorrect Attempts:

CHECK

J

Hint Unavailable

200 g = 0.2 kg

Hint
Clear
Info

Incorrect Attempts:

CHECK

J

Hint Unavailable

200 g = 0.2 kg

total mechanical energy = gravitational potential energy + kinetic energy

= 2.35 J + 0.4 J

= 2.75 J

= 2.35 J + 0.4 J

= 2.75 J

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

The maximum speed occurs at the __ground__, when total mechanical energy is 0% gravitational potential energy and __100% kinetic energy__.

The maximum speed occurs at the __ground__, when total mechanical energy is 0% gravitational potential energy and __100% kinetic energy__. Set total mechanical energy equal to kinetic energy: solve for *v:*

Works is nonconservative, but it must use the distance, *d* of the face of the plane that the box slides on.

Work_{friction} = Force_{friction} × distance

Work

W =

Hint
Clear
Info

Incorrect Attempts:

CHECK

J

Hint Unavailable

Potential Energy at the Top |

Kinetic Energy at the Bottom |

Total Mechanical Energy |

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

Hint Unavailable

Speed at the bottom (v) calculated previously using conservation of energy.

Can be calculated with PE_{top}

Can be calculated with PE

h =

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Work due to friction uses the incline distance = height/(sin60˚)

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hint Unavailable

The maximum height of the second loop is __less__ than the first because the roller-coaster is moving faster due to the conservation of total mechanical energy.

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

The total mechanical energy (TME) of loop 2 equals the total mechanical energy (TME) of loop 1.

TME = KE + PE

TME = KE + PE

Hint
Clear
Info

Incorrect Attempts:

CHECK

%

Hint Unavailable

E =

Hint
Clear
Info

Incorrect Attempts:

CHECK

J

Hint Unavailable

E = (Power)(time) = (100 W)(3600 s) = 360,000 J

P =

Hint
Clear
Info

× 10

Incorrect Attempts:

CHECK

W

Hint Unavailable

P =

Hint
Clear
Info

× 10

Incorrect Attempts:

CHECK

W

Hint Unavailable

(In reality the chosen motor should be considerably more powerful than this).

Energy = Wh, (Watt·hours)

Power = W, (Watt)

Power = W, (Watt)

Hint
Clear
Info

Incorrect Attempts:

CHECK

kJ

Hint Unavailable

First determine the watt-hours 'Wh'
Enegy,

P =

Hint
Clear
Info

Incorrect Attempts:

CHECK

W

Hint Unavailable

Heat is the __transfer__ of energy from a higher to lower temperature.

Temperature is the measure of the average kinetic energy of molecules in a substance.

Temperature is the measure of the average kinetic energy of molecules in a substance.

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hint Unavailable

1) Convection and radiation from the flame through the air

2) Conduction through the metal

3) Convection through the water

4) Convection through the egg if it's liquid, convection if it's solid.

2) Conduction through the metal

3) Convection through the water

4) Convection through the egg if it's liquid, convection if it's solid.

Specific heat capacity is __different__ for all different substances.

+ q, in relation to the energy input into the system.

Thermal equilibrium occurs when the temperatures are the same (average molecular kinetic energies are the same) and there is no net *transfer* of heat energy.

Thermal energy depends on the size of the substance. For example, it is easy for a "cold" swimming pool to contain *more* thermal energy than a hot cup of tea. Besides size, the other factor that matters is the type of substance.

While the __change__ is the same,
∆K = ∆˚C
The magnitudes are not the same,
K ≠ ˚C

T_{f} =

Hint
Clear
Info

Incorrect Attempts:

CHECK

˚C

Hint Unavailable

Heat *lost* is **negative**, therefore q = -100J

Heat is the *movement, or transfer* of energy between things with different temperatures. If the temperature is the same (10˚C), then there is no energy transfer. Therefore there is no heat exchange.

Hint
Clear
Info

Incorrect Attempts:

CHECK

J

Hint Unavailable

4.02 J

Hint
Clear
Info

Incorrect Attempts:

CHECK

cubes

Hint Unavailable

Since the tea and ice cubes reach the same temperature, the heat lost in the tea equals the heat gained in the ice cube.

Let the total mass of ice cubes be 50n (where 'n' is the number of ice cubes, and each cube is 50g) Therefore (rounding up), a minimum of 21 ice cubes are needed.

Let the total mass of ice cubes be 50n (where 'n' is the number of ice cubes, and each cube is 50g) Therefore (rounding up), a minimum of 21 ice cubes are needed.

Hint
Clear
Info

Incorrect Attempts:

CHECK

g

Hint Unavailable

Make sure to plug in 450 g for water, and not 0.45kg

T_{f} =

Hint
Clear
Info

Incorrect Attempts:

CHECK

K

Hint Unavailable

T_{f} =

Hint
Clear
Info

Incorrect Attempts:

CHECK

˚C

Hint Unavailable

The 3 types of oscillation are:

- Longitudinal
- Transverse
- Torsional

For a longitudinal wave, imagine a sound wave traveling *horizontally*. The air particles also oscillate *horizontally*.

For a transverse wave, imagine a boat ('particle') stalled in the ocean with very large waves. The waves travel*horizontally* across the surface of the water, while the boat travels *vertically*.

For a transverse wave, imagine a boat ('particle') stalled in the ocean with very large waves. The waves travel

All the answer choices measure out one wavelength.

Hint
Clear
Info

Point | Name |

B or F | |

D or H | |

vertical height of A to B, or C to D | |

A |

Incorrect Attempts:

CHECK

Hint Unavailable

Point | Name |

B or F | Crest |

D or H | Trough |

vertical height of A to B, or C to D | Amplitude |

A | Node |

Frequency is inversely proportional to period (s), while the SI unit hertz (Hz) is used in place of s^{-1}.

The equilibrium is always located in the center of the oscillation.

Maximum displacement occurs at the furthest points from the equilibrium position. The maximum displacement is also known as the 'amplitude'

Maximum velocity always occurs at the *equilibrium* position.

Maximum acceleration occurs at the two points of maximum displacement (or amplitude), where the pendulum is changing the direction vector.

Many people think that frequency affects speed, but __only wavelength affects the speed__ of a wave that is in existence.

This is for a wave traveling in a medium that has a certain frequency (for sound, think pitch). The speed of this wave can change depending on the medium, but the frequency (or sound, pitch) stays the same, while the wavelength changes. v = ƒ λ

This is for a wave traveling in a medium that has a certain frequency (for sound, think pitch). The speed of this wave can change depending on the medium, but the frequency (or sound, pitch) stays the same, while the wavelength changes. v = ƒ λ

For a fixed frequency, a slower speed (v), would result in a decrease in wavelength (λ): v = ƒ λ

For a fixed frequency, a faster speed (v), would result in an increase in wavelength (λ): v = ƒ λ

When waves travel from a *slow to fast* medium, part of the wave is reflected backwards from the medium boundary and is **upright, or positive**.

When waves travel from a*fast to slow* medium, part of the wave is reflected backwards from the medium boundary and is **inverted, or negative**.

(Actually, the positive and negative aspect depends on the incident orientation of the wave).

When waves travel from a

(Actually, the positive and negative aspect depends on the incident orientation of the wave).

Sound is a longitudinal wave. Longitudinal waves require matter (particles) to oscillate and propagate energy.

The speed of sound is fastest in **dense** materials like iron. (Aside: the speed of sound in iron is approximately 17 times faster than in air).

air at 20˚C is 343m/s, while iron is 5950m/s, sea water is 1530 m/s

Note that the speed of light behaves opposite to sound; light slower in denser mediums (think air versus diamond).

air at 20˚C is 343m/s, while iron is 5950m/s, sea water is 1530 m/s

Note that the speed of light behaves opposite to sound; light slower in denser mediums (think air versus diamond).

- v = speed, (m/s)
- = linear density, (kg/m)
- F
_{T}= Tension, (N)

- m = mass, (kg)
- L = length, (m)

λ =

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

Substitute the linear density equation into the wave speed equation,
And set that equal to the wave equation,

Hint
Clear
Info

Incorrect Attempts:

CHECK

times

Hint Unavailable

Notice that mass and height are both *not* included in the equation for period of a pendulum, therefore mass and height do not have an effect the period of a pendulum.

The only factors that affect the period of a pendulum are__length__ and __gravity__.

The only factors that affect the period of a pendulum are

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

g = 9.81 m/s^{2}

Rearrange, isolate, and solve for length,*l*.

Rearrange, isolate, and solve for length,

Diffraction is the bending of a wave as it passes through a narrow opening or passes by an obstacle.

Refraction is the bending of a wave as it enters a medium with a different density.

- Amplitude
- Frequency
- Wavelength
- ½λ Path Difference

Resonance can occur at a separation distance, when objects are not in contact. (Note that: *mechanical* resonance must have the resonating object in contact with the driving force).

For an object to resonate, a periodic driving force that has the same frequency as the *natural frequency* of an object must exist.

f =

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hz

Hint Unavailable

v = 1 m/s

Solve the absolute value equation like this...

See that there are two possible answers...

See that there are two possible answers...

f' =

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hz

Hint Unavailable

frequency, f is inversely proportional to length, L.

Doubling the length will*decrease* the frequency by a factor of **½**... = 400 Hz

Doubling the length will

f_{1} =

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hz

Hint Unavailable

1

2

3

4

Closed-end pipes use a different formula, where *n* is an odd integer: {1, 3, 5, ...}

Closed pipes have __nodes at the closed end__ and __antinodes at the open end__.

Antinodes are located at open ends.

Closed pipes have these resonant lengths.

Open pipes have: ½λ, λ, 1½λ

Open pipes have: ½λ, λ, 1½λ

Harmonic | Amount of Wavelength in Column | Length (m) | Wavelength (m) |

1 | |||

3 | |||

5 | |||

7 |

Second harmonics are found in **open-end** columns.

L =

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

wavelength = 4.0 m

2^{nd} resonant length = 3^{rd} harmonic

2

λ =

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

You know that the speed of a sound wave depends on the temperature of the air. If the temperature is the same then the speed is the same.

First calculate the speed of sound Since the speaker is in the same room with the same air temperature, then the speed is the same for the subwoofer wave...

First calculate the speed of sound Since the speaker is in the same room with the same air temperature, then the speed is the same for the subwoofer wave...

f =

Hint
Clear
Info

× 10

Incorrect Attempts:

CHECK

Hz

Hint Unavailable

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

Convert the distance travelled for 4 cycles, into the distance for 1 cycle:
Realize that the amplitude is ¼ of the total distance of a cycle.
Therefore the amplitude is 1.25 m

f =

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hz

Hint Unavailable

wavelength = 10 m.

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

v = 5 m/s

t = 20 s

20 s represents twice the distance; there-and-back. The barricade is 50 m from her.

t = 20 s

20 s represents twice the distance; there-and-back. The barricade is 50 m from her.

Hint
Clear
Info

Incorrect Attempts:

CHECK

cycles

Hint Unavailable

ƒ = 0.5 Hz

t = 15 s (This is actually a bit high for real life but w/e)

t = 15 s (This is actually a bit high for real life but w/e)

λ =

Hint
Clear
Info

Incorrect Attempts:

CHECK

m

Hint Unavailable

Each adjacent antinode is ½λ.

v =

Hint
Clear
Info

Incorrect Attempts:

CHECK

m/s

Hint Unavailable

λ = 9 m

The frequency of pitch will go down and it will sound lower as the speed decreases.

Hint
Clear
Info

Incorrect Attempts:

CHECK

˚C

Hint Unavailable

Yes, you can reciprocate both sides of the equation.

f =

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hz

Hint Unavailable

l

f

l

Find f

Hint
Clear
Info

Incorrect Attempts:

CHECK

w/m^{2}

Hint Unavailable

You know that the sound dissipates in a spherical shape, with the distance, being radius, r...

__Givens:__

I_{1} = 0.0008 W/m^{2}

I_{2} = ?

r_{1} = 50 m

r_{2} = 5.0 m

You also know that the power of the speaker system is constant.

I

I

r

r

You also know that the power of the speaker system is constant.

i =

Hint
Clear
Info

Incorrect Attempts:

CHECK

dB

Hint Unavailable

The intensity changes by a factor of ×10 when the decibels change by +10.

1000 = 10^{3} = 10 × 10 × 10...
The change is + 30 dB.

Therefore the new intensity is 60 dB + 30 dB = 90 dB

(90 dB is like the noise level of a food blender)

1000 = 10

Therefore the new intensity is 60 dB + 30 dB = 90 dB

Intensity (W/m^{2}) | decibels (dB) |

10^{-12} | 0 |

10^{-11} | 10 |

10^{-10} | 20 |

10^{-9} | 30 |

10^{-8} | 40 |

10^{-7} | 50 |

10^{-6} | 60 |

10^{-5} | 70 |

10^{-4} | 80 |

10^{-3} | 90 |

10^{-2} | 100 |

10^{-1} | 110 |

10^{0} = 1 | 120 |

10^{1} | 130 |

... | ... |

Hint
Clear
Info

Incorrect Attempts:

CHECK

times louder

Hint Unavailable

Hint
Clear
Info

Incorrect Attempts:

CHECK

dB

Hint Unavailable

Solve for the higher intensity, dB_{H}
When solving for a variable in the exponent, take the log of both sides of the equation. This will drip the exponent, multiplied down in-front...

Charged (positive or negative) atoms are called ions.

Not necessarily. An object with a *neutral* charge might have a high number of positively charged particles within it, but with an *equal number of negatively charged particles*.

An object is positively charged when: (number of positive charges) > (number of negative charges)

An object is positively charged when: (number of positive charges) > (number of negative charges)

Attraction of Electrons | Material |

High attraction | Copper |

↕ | Ebonite |

↕ | Plastic |

↕ | Fur |

↕ | Glass |

Low attraction | Acetate |

Flow of electrons only.

The positively charged rod will attract the negative electrons into the object (positive charges in the ground). When the grounding is removed, the negative charges will be "trapped" in the object.

When the rod is removed, since the grounding is still connected to the object, the charges redistribute evenly (neutral).

Placing a charged rod in contact will charge the object.

Placing a charged rod in contact will __not__ charge the object when it is grounded. This is because the grounding can be considered as an infinite supply (or sink) of positive and negative charges, which will always make both the rod and the object uncharged (neutral) when connected and grounded.

The result is F_{e} decreases by a factor of ½.

The charge on a proton is equal in magnitude to the charge on an electron, with an opposite sign.

Find N We cannot determine the total number of protons, we can only say that there are 17

For example, if there were 18 protons and 1 electron, the net charge would still be +2.72 × 10

Element | Total Number of Protons |

Carbon | 6 |

Sodium | 11 |

Silicon | 14 |

Calcium | 20 |

Q =

Hint
Clear
Info

× 10

Incorrect Attempts:

CHECK

C

Hint Unavailable

t =

Hint
Clear
Info

× 10

Incorrect Attempts:

CHECK

s

Hint Unavailable

Q = = -1.6 × 10^{-17}C

i = 1.0 × 10^{-10}A

i = 1.0 × 10

Other way around:

Alternating current is used in household wall outlets, and direct current is used in batteries.

Alternating current is used in household wall outlets, and direct current is used in batteries.

W =

Hint
Clear
Info

Incorrect Attempts:

CHECK

J

Hint Unavailable

2 mA = 2 × 10^{-3} A

1 minute = 60 s

1 minute = 60 s

Conventional current is the flow of positive charges. The longer side of the cell is positive and the positive charges flow from the positive terminal, to the negative terminal.

Batteries store electric potential energy per unit of charge (electron).

EMF is an outdated term. Voltage is an unofficial term. The most correct term to use in place of "voltage" and EMF is __potential difference__.

This is almost true. However, voltage (electric potential) is __electric potential energy, in __*Joules* **per unit of charge, ***q*. See that voltage is J/C.

So, voltage is electric potential (and not electric potential energy).

So, voltage is electric potential (and not electric potential energy).

- R
_{T}= R_{1}+ R_{2}+ ... - V
_{T}= V_{1}+ V_{2}+ ... - V
_{T}= V_{1}= V_{2}= ... - i
_{T}= i_{1}+ i_{2}+ ... - i
_{T}= i_{1}= i_{2}= ...

Hint
Clear
Info

Incorrect Attempts:

CHECK

V

Hint Unavailable

The total increase in electric potential (voltage) is equal to the total decrease in electric potential across one path in a circuit.

Hint
Clear
Info

Incorrect Attempts:

CHECK

V

Hint Unavailable

The total increase in electric potential (voltage) is equal to the total decrease in electric potential across one path in a circuit.

Hint
Clear
Info

Incorrect Attempts:

CHECK

A

Hint Unavailable

The current at the start of a junction is equal to the current at the end point of that junction.

Hint
Clear
Info

Incorrect Attempts:

CHECK

A

Hint Unavailable

The current at the start of a junction is equal to the current at the end point of that junction.

Hint
Clear
Info

i_{1} = A

V_{2} = V

V_{3} = V

i_{3} = A

V

V

i

Incorrect Attempts:

CHECK

Hint Unavailable

Hint
Clear
Info

V_{1} = V

i_{3} = A

i_{1} = A

V_{3} = V

R_{1} = Ω

R_{2} = Ω

R_{3} = Ω

i

i

V

R

R

R

Incorrect Attempts:

CHECK

Hint Unavailable

Hint
Clear
Info

V_{2} = V

i_{1} = A

i_{2} = A

R_{2} = Ω

V_{3} = V

V_{4} = V

R_{4} = Ω

i_{3} = A

i_{T} = A

i

i

R

V

V

R

i

i

Incorrect Attempts:

CHECK

Hint Unavailable

Magnetic field lines are not straight, nor are they parallel. Field lines curve in 3D space.

The north pole of the permanent magnet induces a south pole at the nearest end of the iron rod...
(1) = S and (2) = N

True.

This happens when a magnet is brought in close proximity to an *even stronger* magnet. The stronger magnet has a stronger magnetic field that dominates and aligns the dipole direction of the atoms in the weaker magnet. This reverses or switches the poles in the weaker magnet.

Breaking the magnet in half *conserves the magnetic dipole*, it just divides the magnet in half and makes two separate magnets.

For a certain material, a magnet can only be polarized up the point where *all dipoles are aligned (in the same direction)*. There is a saturation point for every magnetic material where no more atomic dipoles can be aligned.

(Changing the material or increasing the size of the magnet doesn't count).

(Changing the material or increasing the size of the magnet doesn't count).

Kinetic molecular theory of the atoms in a magnet explains that the atomic dipoles experience internal forces that, in combination with the magnetic poles, can demagnetize the magnet over time.

(Note that magnets can be stored in a way to maintain their charge).

(Note that magnets can be stored in a way to maintain their charge).

True. Check it out...

While it is the delocalized (free) electrons in a metal that carries a current, by convention the flow of positive charges in the opposite direction is used.

Increasing the diameter of the coil (making a bigger coil) spreads the magnetic field lines apart, decreasing the density of the field lines, lowering the magnetic field strength.

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hint Unavailable

Use the right hand grip rule around one of the coils. (See that the current comes from the side of the source with the longer bar)

To the left:

To the left:

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hint Unavailable

Use the right hand grip rule... (See that the current comes out at the top and goes in at the bottom)

To the right:

To the right:

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hint Unavailable

Conventional current points into the page. Magnetic field is always directed from N to S, which in this case is to the left. Using the left hand rule for conventional current, the force is directed __upwards__.

A coil experiences an induced current when the magnetic field passing through it varies in magnitude or direction.

True. Current is produced when the magnet is *moving* through the wire coil, but not produced when the magnet is stationary.

False. Moving the magnet with greater speed will induce more current. No speed (speed of zero) will induce no current.

False.

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hint Unavailable

Basically, the induced current will form in the direction that creates a magnetic field through the solenoid that *repels* the movement of the magnet. The energy required to push the magnet through the solenoid, against this repulsive force is inducing the energy that is "created" in the circuit.

Get the correct current direction using the__left hand grip rule (thumb = current, fingers = magnetic field)__ when the magnet moves towards.

Get the correct current direction using the

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hint Unavailable

Basically, the induced current will form in the direction that creates a magnetic field through the solenoid that *repels* the movement of the magnet. The energy required to push the magnet through the solenoid, against this repulsive force is inducing the energy that is "created" in the circuit.

Get the correct current direction using the__left hand grip rule (thumb = current, fingers = magnetic field)__ when the magnet moves towards.

Get the correct current direction using the

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hint Unavailable

Basically, the induced current will form in the direction that creates a magnetic field through the solenoid that *repels* the movement of the magnet. The energy required to push the magnet through the solenoid, against this repulsive force is inducing the energy that is "created" in the circuit.

Get the correct current direction using the__right hand grip rule (thumb = current, fingers = magnetic field)__ when the magnet moves away.

Get the correct current direction using the

Hint
Clear
Info

Incorrect Attempts:

CHECK

Hint Unavailable

Basically, the induced current will form in the direction that creates a magnetic field through the solenoid that *repels* the movement of the magnet. The energy required to push the magnet through the solenoid, against this repulsive force is inducing the energy that is "created" in the circuit.

Get the correct current direction using the__right hand grip rule (thumb = current, fingers = magnetic field)__ when the magnet moves away.

Get the correct current direction using the

The slip rings used in an AC generator maintain continual contact between the rotating loop and the rest of the circuit, causing an alternation in current direction.

A DC generator setup uses a*split-ring* commutator to connect the loop to the rest of the circuit. This maintains the same direction of current in the circuit.

A DC generator setup uses a

The ratio of emf's in the circuits is equal to the ratio of the number of turns.

**p** is primary, **s** is secondary.
The secondary voltage is half the primary voltage. Therefore this is a **step down transformer**.

V =

Hint
Clear
Info

Incorrect Attempts:

CHECK

V

Hint Unavailable

V is the voltage, N is the number of turns.

i =

Hint
Clear
Info

Incorrect Attempts:

CHECK

A

Hint Unavailable

Loading and rendering MathJax, please wait...

PRESS START

★ WORK FOR IT & LEVEL UP

×
# CLASS PAGE SETTINGS

## Streamlined Question View

## Level of Difficulty

Question Fonts

Monospace

Helvetica

Comic

8-bit

POW!

Georgia

Garamond

Print Questions

Normal, B&W, Ink Saver

Compact, B&W, Ink Saver

Show Videos

Show Solutions

Show Level Badges

Sound

×
# KEYBOARD SHORTCUTS

- class settings
- keyboard shortcuts
- drawing tools
- table of contents
- fullscreen
- close
- previous question
- next question