Brainscape's Knowledge GenomeTM

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


See full index

A-Level Physics > [AS] Forces and Energy > Flashcards

[AS] Forces and Energy Flashcards

1
Q

What is Newton’s First Law?

A

The velocity of an object will not change unless a resultant force acts on it

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

What is Newton’s Second Law?

A

Acceleration is proportional to resultant force

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

What is Newton’s Third Law?

A

Every force has an equal and opposite reaction force

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

What kind of friction acts between solid surfaces?

A

dry friction / contact friction

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

What kind of friction acts between fluid surfaces?

A

drag / fluid resistance / air resistance

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

What do you call a force that opposes motion?

A

Friction

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

What does friction convert kinetic energy into?

A

Heat and Sound

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

What is lift?

A

An upwards force on an object moving through a fluid.

It acts perpendicular to the direction of the fluid’s flow

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

What force acts perpendicular to the direction a fluid flows in?

A

Lift

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

What causes lift?

A

Fluid flowing changes direction as it moves over object’s shape

Difference in pressure on either side of the object

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

What two forces are equal at terminal velocity?

A

Friction and Driving Force

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

What are the two conditions for an object reach terminal velocity?

A
  1. a constant Driving Force

2. a Frictional Force that increases with speed

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

How can you increase a vehicle’s maximum speed?

A
  1. increase the Driving Force (increase engine size)

2. reduce the Frictional Force (more streamlined body)

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

Describe how a skydiver reaches terminal velocity

A
  1. Skydiver initially accelerates due to gravity
  2. Air resistance increases until it equals his weight (terminal velocity)
  3. The parachute opens, increasing air resistance
  4. He decelerates until he is slow enough for air resistance to equal weight
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does ‘resolving a force’ mean?

A

Splitting it into perpendicular components

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

What is always true for three coplanar forces acting on a point in equilibrium?

A

The three forces can be drawn as a closed triangle

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

For a force triangle, what is true about the direction of the forces?

A

You can trace their directions around the triangle in a loop

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

How do you find the resultant force of two component forces?

A

Add them together

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

What is density?

A

Mass per unit volume

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

What is an object’s density dependent on?

A

The material it is made of

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Under what condition will a solid object float in a fluid?

A

If its density is lower than the fluid’s

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

What is pressure?

A

Force per unit area

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

What is pressure measured in?

A

pascals (Pa)

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

What is one pascal equivalent to?

A

Nm^-2

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

What are the SI base units of the Newton?

A

kg⋅m⋅s^-2

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

What is the extra pressure on an object in a depth in a fluid equal to?

A

p = hρg

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

What is upthrust?

A

An upward force a fluid exerts on objects that are fully or partially submerged in the fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is Archimedes’ Principle?

A

Upthrust is equal to the weight of the displaced fluid

29
Q

Does the mass of an object change when g changes?

30
Q

Does the weight of an object change when g changes?

31
Q

What is weight a measure of?

32
Q

What is weight equal to?

33
Q

Where should you assume all of the mass of an object acts?

A

Centre of mass

34
Q

When will an object topple over?

A

If the centre of mass is outside its base

35
Q

What is a moment?

A

The turning effect of a force

36
Q

How do you calculate the moment?

A

Force × perpendicular distance from picot

37
Q

What happens if the moments are imbalanced?

A

The object will turn

38
Q

What is the principle of moments?

A

Sum of clockwise moments

sum of anticlockwise moments

39
Q

What is a couple?

A

Two equal-size coplanar forces acting parallel to each-other in opposite directions

40
Q

How do you calculate the moment of a couple?

A

Size of one of the forces × distance between them

41
Q

How do you calculate momentum?

A

Mass × velocity

42
Q

Is momentum conserved?

43
Q

What is an elastic collision?

A

Momentum and kinetic energy are conserved

44
Q

What is an inelastic collision?

A

Momentum is conserved

Some kinetic energy is converted to other forms (e.g. sound)

45
Q

What is impulse?

A

The change in momentum

46
Q

How do you calculate impulse from a graph?

A

Area under a force-time graph

47
Q

What is the area under a force-time graph?

48
Q

What is a Crumple zone?

A

An area at the front/rear of a car designed to crumple on impact

49
Q

How does a Crumple zone reduce risk?

A

Absorb some of the car’s kinetic energy

Increase time taken to slow down, reducing force

50
Q

When is work done?

A

When energy is transferred?

51
Q

What is done when energy is transferred?

52
Q

What happens to kinetic energy when an object stops moving?

A

It is transferred to another form of energy

53
Q

Why do you need a force to move an object?

A

To overcome another force

54
Q

Define work done

A

The amount of energy transferred from one form to another when a force causes movement

55
Q

What is an equation for work done with force and distance?

A

Work done = Force × distance

56
Q

How do you calculate work done from a graph?

A

Area under a force-displacement graph

57
Q

What is the area under a force-displacement graph?

58
Q

Define power

A

The rate that work is done

Energy transferred per second

59
Q

What is the unit of Power?

60
Q

What is kinetic energy?

A

Energy an object has due to movement

61
Q

What is gravitational potential energy?

A

Energy an object has due to its position in a gravitational field

62
Q

How is GPE related to Work?

A

GPE gained =

work done moving through a height

63
Q

What is change in kinetic energy of an object equal to?

A

Work done on the object

64
Q

What it the Principle of Conservation of Energy?

A

Energy can’t be created or destroyed. It can only be transferred between forms

65
Q

What is lost energy?

A

Energy transferred to a waste form

66
Q

Is it possible for no energy to be lost?

67
Q

What causes heat loss?

68
Q

What is efficiency?

A

The ratio of useful energy output to total energy input

A-Level Physics (13 decks)

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