Brainscape's Knowledge GenomeTM

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


See full index

Physics P2 > Forces > Flashcards

Forces Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

What do objects do in terms of forces?

A

Exert equal and opposite forces on each other-sometimes known as action reaction forces

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

If a car hits a barrier what does the barrier exert on the car in terms of force?

A

The barrier exerts a force on the car that is equal in size and in the opposite direction

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

In what direction does weight always act?

A

Downward

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

What is the resultant force?

A

Is the single force that would have the same effect on the object as all the original forces acting together

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

What does could it mean if the resultant force on an object is zero?

A

If the object is at rest, it will stay at rest

If the object is moving, it will carry on moving at the same speed in the same direction

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

If an object is accelerating what 3 things could it be doing?

A

Speeding up
Slowing down
Changing direction

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

When the resultant force of an object is not zero, what will happen to the object?

A

It will accelerate in the direction of the force

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

What could happen if the resultant force is not at zero?

A

If the object is at rest, it will accelerate in the direction of of the resultant force
If the object is moving in the same direction as the resultant force, it will accelerate in that direction
If the object is moving in the opposite direction to the resultant force it will decelerate

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

What is the unit of resultant force?

A

Newtons

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

What is the resultant force of a 4n force and a 3n force acting in the same direction?

A

7n in the same direction as the two forces

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

What doe s a resultant force always cause?

A

An acceleration, if there is no acceleration the resultant force must be zero

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

What equation is used to calculate the resultant force?

A

F=MxA

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

What is mass measured in?

A

Kg

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

What is weight measured in?

A

Newtons

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

The greater the resultant force, what does that mean about the acceleration?

A

The acceleration is greater

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

If the mass of an object is large, what does that mean about the size of the force needed?

A

The bigger the mass, the bigger the force needed to give it a particular acceleration

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

What is the resultant force on a car travelling at a steady speed on a straight horizontal road?

A

Zero as a steady speed mean no acceleration so no resultant force

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

What happens to the acceleration of an object as the resultant force on it decreases?

A

Acceleration decreases

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

The faster the speed of a vehicle…

Braking distance

A

The bigger the deceleration need to stop it therefore a bigger braking distance needed

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

What is the stopping distance?

A

The distance a vehicle travels during the drivers thinking distance plus the distance travels under the braking distance

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

What is the thinking distance?

A

The distance travelled by the vehicle in the time it takes the driver to react

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

What is the braking distance?

A

The distance travelled by a vehicle during the time it’s brakes act

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

What can affect the thinking distance?

A

Alcohol

Drugs

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

What can affect braking distance?

A

Poorly maintained roads
The condition of the car eg worn tyres or worn breaks will increase braking distance
Weather conditions

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

What is the relationship between stopping distance, thinking distance and braking distance?

A

Stopping distance= thinking + braking distance

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

What is the weight of an object?

A

The force of gravity on the object

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

What is mass?

A

The quantity of matter in it

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

An object acted on by only gravity accelerates by how much?

A

10m/s

29
Q

If an object falls freely what is the resultant force acting on it?

A

The force of gravity

30
Q

When an object falls through a liquid what force does the liquid exert on the object and what effect does it have?

A

A drag force which restricts its motion

31
Q

Why does an object dropped in a fluid initially accelerate?

A

There is a resultant force acting on it

32
Q

What eventually halogens to an object falling in a fluid?

A

It reaches a terminal velocity as the resultant force becomes zero

33
Q

What are forces measured in?

A

Newtons

34
Q

What is the extension of a spring?

A

The increase in length from the original

35
Q

What does elastic mean?

A

A material is elastic if it is able to regain its shape after it has been squashed or stretched

36
Q

If you plot a graph of extension against force applied for a spring what sort of line will we Obtain?

A

A line that is directly proportional which passes through the origin

37
Q

What is limit of proportionality?

A

The limit for hooked law applied to the extension of a stretched Spring

38
Q

What does hooked law state?

A

The extension is directly proportional to the force applied provided the limit of proportionality is not exceeded

39
Q

If a spring is stiff what does that mean about its spring constant?

A

The stiffer the spring, the greater the spring constant

40
Q

What is spring constant measured in?

A

N/M

41
Q

What happens when an elastic object is stretched?

A

Work is done this is stored as elastic potential energy

42
Q

What happens when the stretching force of a string is removed?

A

The stored energy is released

43
Q

How can we tell when a spring has exceeded its limit of proportionality?

A

The graph of extension force against is no longer a straight line

44
Q

What is fuel economy?

A

If you reduce the speed of a vehicle it reduces the amount if fuel it uses to travel a particular distance

45
Q

What Improves fuel Economy?

A

Reducing air resistance makes a vehicle more streamlined (fitting a wind deflector)

46
Q

What are average speed cameras?

A

Cameras that are linked in pair that calculate the average speed of a vehicle to catch out drivers who slow down then speed up for cameras

47
Q

What do anti skid surfaces do?

A

They refuse or prevent skidding. They are rougher than normal road surfaces, increasing the friction between the tyres and the road. They are used

48
Q

What can a force do?

A

Change the shape of an object or change its state of rest or motion

49
Q

What force makes a car move?

A

Engine force or motive force

50
Q

If the resultant force is zero what could that mean about the forces acting on it?

A

They are balanced

51
Q

What is the total resultant force if the forces are in the same direction?

A

Their sum is the resultant force

52
Q

What is the total resultant force if the forces are in the opposite direction?

A

The difference in the force subtract

53
Q

Why will a falling object accelerate at first?

A

The weight is greater than the drag force

54
Q

As the object falls faster what will happen?

A

The drag forces increase so the acceleration will decrease

55
Q

What happens when the 2 forces on a falling object balance?

A

The acceleration is zero and the terminal velocity is reached

56
Q

Describe the drag force on a parachutist

A

At first the drag force is due to the parachutist alone

Later on the drag force is due to the parachute

57
Q

Why do rubber bands and polythene strips not obey Hookes law?

A

They have a low limit of proportionality and so do not produce a straight line graph

58
Q

The force of the friction of the ground on the tyre is in the ….

A

Forward direction

59
Q

The force of the tyre on the ground is in the ….

A

Reverse direction

60
Q

The velocity …. If the resultant force is in the ….. Direction to the velocity

A

Decrease

Opposite

61
Q

The velocity increases If the resultant force is in the ….. Direction to the velocity

A

Same

62
Q

The …. The mass of an object the …. It’s acceleration for a given …

A

Greater
Smaller
Force

63
Q

What is the thinking distance equal to?

A

The cars speed multiplied by the drivers reaction time. It is proportional to the cars speed

64
Q

What is the breaking distance equal to?

A

The average speed of the car during the braking multiplied by the breaking time. The breaking distance is proportional to the square of the cars speed

65
Q

What is gravitational field strength usually on earth?

A

10n/kg

66
Q

Drag force increased with …

A

Speed

67
Q

The acceleration of an object decrease as it falls because …

A

The drag forces increases as it speeds up

68
Q

What is terminal velocity?

A

When the resultant force becomes zero so no longer accelerates

Physics P2 (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions