Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Study > Physics Midterm Study > Flashcards

Physics Midterm Study Flashcards

1
Q

What is the definition of speed?

A

Speed is how fast an object is moving (the distance traveled every second).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How does speed differ from velocity?

A

Velocity requires a direction while speed does not; average velocity is calculated with displacement rather than with distance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

If a person runs with a constant speed of 4 m/s for 20 seconds, how far will they move?

A

d = st = 4 m/s * 20 s = 80 m

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

If a person runs with a constant speed of 5 m/s, how long will it take to move 1200 m?

A

t = ds = 1200 m / 5 m/s = 240 s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the definition of acceleration?

A

The rate at which the velocity of an object is changing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

If a motorcycle accelerates from rest with a rate of 7 m/s², what will its speed be after 3 seconds?

A

vf = vi + at = 0 + 7(3) = 21 m/s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

If a motorcycle travelling at 45 m/s ‘forward’ suddenly accelerates ‘backward’ at 5 m/s², how long will it take to stop?

A

t = (vf - vi) / a = (0 - 45) / -5 = 9 s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does the slope of a position vs time graph represent?

A

The slope of a position vs. time graph represents the object’s velocity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does the slope of a velocity vs time graph represent?

A

The slope of a velocity vs. time graph represents the object’s acceleration.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is true about the acceleration rate of objects of different mass in freefall, ignoring air resistance?

A

All masses accelerate at the same rate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How long does it take for an object to free fall (from rest) from a height of 50 meters?

A

t = √(2x/a) = √(2(50)/10) = 3.16 sec

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

If an object free falls (from rest) for 6 seconds, how far has it fallen?

A

x = vit + (1/2)at² = (1/2)(10)(6²) = 180 m

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

When an object is tossed straight upward, what is its velocity and acceleration at the peak of its motion?

A

Velocity at peak is zero; acceleration rate at peak is 10 m/s² downward.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is inertia?

A

Inertia is the resistance an object has to changes in motion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the quantity we use to measure inertia?

A

Mass.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a ‘force’?

A

A force is simply a push or pull on an object.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is a ‘net force’?

A

Net force is the sum of all forces acting on an object (with directions taken into account).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

State Newton’s 1st Law.

A

An object will remain in constant motion in the absence of a nonzero net force acting on it.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does it mean for an object to be ‘in equilibrium’?

A

Equilibrium is the state of balanced forces, where the net force is zero.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the two states of motion possible for an object in equilibrium?

A
  • At rest * Moving with constant velocity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

State Newton’s 2nd Law in words.

A

The acceleration of an object is directly proportional to the net force acting upon it and inversely proportional to its mass.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

State Newton’s 2nd Law as an equation.

A

a = F/m

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What does it mean for two variables to be ‘directly proportional’?

A

If one variable increases, the other variable increases proportionally.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What does it mean for two variables to be ‘inversely proportional’?

A

If one variable increases, the other variable decreases proportionally.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

If the net force acting on an object is doubled, what will happen to its acceleration rate?

A

It will double.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

If the mass of an object experiencing a constant net force is suddenly doubled, what will happen to the acceleration rate?

A

It will be cut in half.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Distinguish between mass and weight.

A
  • Mass: Amount of matter in an object, measured in kg. * Weight: Magnitude of the force exerted by the Earth on the object, measured in N.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

If a person goes to the Moon, does their mass change?

A

Mass does not change.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

If a person goes to the Moon, does their weight change?

A

Weight changes dramatically.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How do we calculate the weight of an object here on Earth?

A

W = Fg = mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the weight of a 60 kg object here on Earth?

A

W = mg = 60 kg * 10 m/s² = 600 N

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the mass of an object that weighs 750 N on Earth?

A

m = W/g = 750 N / 10 m/s² = 75 kg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

An object experiences a forward force of 15 N and a backward force of 13 N. What is the net force on the object?

A

F = Ff - Fb = 15 N - 13 N = 2 N forward

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

A 3 kg object experiences a forward force of 25 N and a backward force of 13 N. At what rate will the object accelerate?

A

F = Ff - Fb = 25 N - 13 N = 12 N forward; a = F/m = 12 N / 3 kg = 4 m/s² forward

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is a ‘normal’ or ‘supporting’ force?

A

The force exerted by a surface on something being supported by that surface, always perpendicular to the surface.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is momentum?

A

Momentum is the product of an object’s mass and velocity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

How do we calculate momentum?

A

p = mv

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

If the velocity of a mass triples, what happens to its momentum?

A

Momentum also triples.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is impulse?

A

Impulse is the product of a force and the time during which it acts.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

How do we calculate impulse?

A

J = Ft

41
Q

What is true about the impulse and change in momentum?

A

Impulse is always equal to the change in momentum.

42
Q

Under what condition is the momentum of a system conserved?

A

There is no impulse acting on the system (meaning no net force).

43
Q

What is recoil?

A

The backward velocity given to an object when it shoots another object forward.

44
Q

How does a rocket accelerate in outer space?

A

By pushing exhaust gases out the end of the rocket.

45
Q

What is the difference between ‘revolution’ and ‘rotation’?

A
  • Revolution: Moves around an external object (e.g., Earth around the Sun). * Rotation: Spins on its axis (e.g., Earth spinning on its axis).
46
Q

When an object moves in a circle, what is the angle between the velocity vector and the acceleration vector?

A

90° (perpendicular).

47
Q

What happens to the acceleration of an object in uniform circular motion if the object’s speed doubles but the radius stays constant?

A

The acceleration would quadruple.

48
Q

What did Newton discover about gravitation?

A

Gravitation is universal and directly proportional to the masses of the objects.

49
Q

What is the angle between the velocity vector and the acceleration vector in uniform circular motion?

A

90° (perpendicular)

50
Q

If an object’s speed doubles while its radius stays constant, what happens to its acceleration?

A

The acceleration quadruples (becomes four times more)

51
Q

What happens to the acceleration if the radius is doubled while speed remains constant?

A

The speed is cut in half (becomes two times less)

52
Q

What did Newton discover about gravitation?

A

Gravitation is universal and directly proportional to the masses of the objects and inversely proportional to the square of the distance between them.

53
Q

Write Newton’s Law of Universal Gravitation formula.

A

Fg = Gm1m2/d²

54
Q

If the distance between two masses doubles, what happens to the gravitational force between them?

A

The force is quartered (four times less)

55
Q

What happens to the gravitational force if the distance triples?

A

The force is one-ninth as much (nine times less)

56
Q

What happens to the gravitational force if the distance is cut in half?

A

The force is quadrupled (four times more)

57
Q

When a 600 kg object and a 5 kg object attract each other gravitationally, which object experiences the greater amount of force?

A

They both experience the same force!

58
Q

If a person climbs a very tall ladder to a height equal to one Earth radius, how does their weight change?

A

Their weight would be four times less (one quarter as much)

59
Q

What is the value of G, and what does this small value indicate about the strength of gravity?

A

6.67 x 10⁻¹¹, indicating that gravity is very weak compared with other fundamental forces.

60
Q

What is a ‘gravitational field’?

A

A field of attraction surrounding any mass, stronger at points closer to the mass and weaker at points farther from the mass.

61
Q

What does Kepler’s 1st law say about the paths of planets as they orbit the Sun?

A

A planet orbits in an ellipse with the Sun at one focus point.

62
Q

What does Kepler’s 2nd law state?

A

A planet orbiting the sun sweeps out equal areas in equal times.

63
Q

What is Kepler’s 3rd Law?

A

The square of the period of a planet’s orbit is proportional to the cube of its orbital distance.

64
Q

How does a planet’s average distance from the Sun affect its period?

A

Planets that are further from the Sun have longer periods.

65
Q

At what point in a planet’s elliptical orbit around the Sun is potential energy greatest?

A

At aphelion (farthest from the Sun)

66
Q

At what point is kinetic energy greatest in a planet’s orbit?

A

At perihelion (closest to the Sun)

67
Q

How do we calculate the work done on an object by a force?

A

Work is force multiplied by distance. W = Fd

68
Q

What work does a woman do on a box if she pushes it 5 meters with a force of 200 N?

A

W = 200 * 5 = 1000 J

69
Q

Under what circumstances is work positive?

A

When force and distance point in the same direction.

70
Q

When is work negative?

A

When force and distance point in opposite directions.

71
Q

When is work zero?

A

When there is no distance, no force, or if the force and distance are perpendicular.

72
Q

When an object is lifted upward, does the force exerted by Earth do positive or negative work?

A

Negative work.

73
Q

When an object falls, does the force exerted by Earth do positive or negative work?

A

Positive work.

74
Q

What is the net work done on a crate pushed with a 100 N force against 80 N of friction over 6 meters?

A

120 J

75
Q

How much work does a waiter do on a tray of food while moving at constant speed?

A

Zero.

76
Q

How much work does a weightlifter do on a 15 kg dumbbell raised 2 meters?

A

300 J

77
Q

What is the definition of power?

A

The rate at which work is done. P = W/t

78
Q

How much work does a 60 kg girl do to raise her body 5 m in 8 seconds?

A

2500 J; Power output is 312.5 W

79
Q

If the same girl runs up the same stairs in 4 seconds, how does her power output compare?

A

Her power output will increase.

80
Q

What is the power output of a machine that does 5000 J of work in 30 seconds?

A

166.7 W

81
Q

What is kinetic energy and how do we calculate it?

A

Energy associated with motion. KE = (1/2)mv²

82
Q

Can kinetic energy ever be negative?

A

No.

83
Q

If an object moves twice as fast, by what factor has its kinetic energy changed?

A

Four times more.

84
Q

If the net work done on an object is positive, what happens to its kinetic energy?

A

KE will increase.

85
Q

If the net work done is negative, what happens to kinetic energy?

A

KE will decrease.

86
Q

If the net work done is zero, what happens to kinetic energy?

A

KE will not change.

87
Q

What is gravitational potential energy and how is it calculated?

A

Energy associated with position (height). PE = mgh

88
Q

Can gravitational potential energy be negative?

A

Yes, if below the reference level.

89
Q

If a ball is dropped from rest, how do its PE and KE compare just before it strikes the ground?

A

They are equal (conservation of energy).

90
Q

What is total mechanical energy?

A

The sum of potential and kinetic energy.

91
Q

What happens to a bullet’s PE and KE as it rises?

A

PE increases while KE decreases; KE is zero at maximum height.

92
Q

When an object experiences friction and air resistance, is total mechanical energy conserved?

A

No, it reduces TME.

93
Q

Where does the ‘lost’ energy from friction and air resistance go?

A

Converted to thermal energy.

94
Q

What is the definition of Work?

A

The product of force and distance.

95
Q

What is the abbreviation for Power?

A

P

96
Q

What is the unit for Kinetic Energy?

A

J

97
Q

What is the abbreviation for Gravitational Potential Energy?

A

Ug

98
Q

What is the unit for Total Mechanical Energy?

A

J

Study (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions