Brainscape's Knowledge GenomeTM

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


See full index

gcse triple science physics > Topic 5: Forces > Flashcards

Topic 5: Forces Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards GCSE Religious Studies - Edexcel Route A flashcards AP® Physics flashcards GCSE Religious Studies - Eduqas Route A flashcards GCSE Geography - AQA flashcards Biology 101 flashcards GCSE Religious Studies - Edexcel Route B flashcards GCSE Religious Studies - Eduqas Route B flashcards
1
Q

What is a force?

A

A force is a push or pull object that is caused by it interacting with something

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

What is a non-contact force?

A

When the objects do not need to be touching for the force to act

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

What is a contact force?

A

When two objects have to be touching for the force to act

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

What is an interaction pair?

A
  • an interaction pair of forces that are equal and opposite and act on two interacting objects
  • there is a force on both objects when two objects interact (basically Newton’s Third Law)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are vector quantities? Give some examples

A

Vector quantities have a magnitude and a direction e.g. force, velocity, displacement, acceleration, momentum etc.

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

What are scalar quantities? Give some examples

A

Scalar quantities have only magnitude and no direction e.g. speed, distance, mass, temperature, time, etc.

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

Describe how vectors are usually presented

A

Vectors are usually represented by an arrow - the length of the arrow shows the magnitude, and the direction of the arrow shows the direction of the quantity

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

What does friction do?

A

If an object has no force propelling it along, it will always slow down and stop because of friction

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

How does friction work?

A

Friction always acts in the opposite direction to movement

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

Why does the driving force need to balance the frictional forces?

A

To travel at steady speed

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

When will friction occur?

A

You get friction between two surfaces in contact, or when an object passes through a fluid (drag)

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

What does terminal velocity depend on?

A

Shape and area

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

What is gravity and how does it affect falling objects?

A

Gravity is the accelerating force acting on all objects and it would make them all fall at the same rate if it wasn’t for air resistance

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

How does gravity affect falling objects on the moon?

A

On the moon where there’s no air, hamsters and feathers dropped simultaneously will hit the ground together

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

How does air resistance on earth affect falling objects?

A

Air resistance causes objects to fall at different speeds

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

What is terminal velocity determined by?

A

The terminal velocity of any object is determined by its drag in comparison to its weight

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

What does the frictional force depend on?

A

Shape and area

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

What does it mean when objects fall through fluids? What do they reach?

A

Terminal velocity

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

What happens to falling objects when they first set off?

A

The force of gravity is much more than the frictional force slowing it down, so it accelerates

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

What happens to friction as speed increases?

A

As speed increases, the friction builds up

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

As friction builds up when speed increases, how does this affect the acceleration of an object?

A

This gradually reduces the acceleration until the frictional force is equal to the accelerating force, so the resultant force is zero

22
Q

What happens to drag when speed increases?

A

Drag increases as speed increases

23
Q

What is drag? Give an example

A

Drag is the resistance you get in a fluid (a gas or a liquid) e.g. air resistance

24
Q

What is the most important factor for reducing drag?

A

Keeping the shape of the object streamlined - where the object is designed to allow fluid to flow easily across it, reducing drag
(Parachutes work in the opposite way - they want as much drag as they can get)

25
Q

Give an example where frictional forces from fluids always increases with speed

A
  • a car has much more friction to work against when travelling at 70 mph compared to 30 mph
  • so at 70 mph, the engine has to work more harder just to maintain a steady speed
26
Q

What is moment?

A

The rotational or turning effect of a force

27
Q

How does the distance between the pivot and where the force is being exerted, affect the force itself?

A

The closer the force is being applied to the pivot, the greater the force applied needs to be

28
Q

What do levers do?

A

Transmit the turning effect of a force

29
Q

What does the gear system allow to do?

A

Gears transmit turning effects
The gear system allows the turning effect of the engine to be transmitted to the wheels
Gears turn in opposite directions

30
Q

What is pressure

A

Pressure is the force per unit of area

31
Q

What is the perpendicular force?

A

Component of the force which is at right angles to the surface it’s colliding with

32
Q

Describe how an object sinks

A
  • when an object is submerged into the water
  • forces will be exerted onto it from different directions
  • there is a resultant force pushing the object upwards known as upthrust
  • if the weight of the object is greater than upthrust, the object will sink
33
Q

Describe how an object floats

A
  • when an object is submerged into the water
  • forces will be exerted onto it from different directions
  • there is a resultant force pushing the object upwards known as upthrust
  • if upthrust is greater than the weight of the object, the object will float
34
Q

How does the density of the object affect whether the object can float or not?

A

If the object’s density is greater than the density of the liquid, the object will sink
If the density of the liquid is greater than the object’s density, the object will float

35
Q

Describe how pressure is affected when really high up in the air

A

The density of the gas particles is highest near the earth’s surface, so the pressure gets smaller the further away from the earth
When in the air, there are fewer particles and weight will be smaller
Air is thinner the higher up you are

36
Q

How is terminal velocity reached?

A
  • there’s a maximum forward force
  • as speed increases, air resistance increases
  • forward force = air resistance
  • resultant force equals zero
  • terminal velocity reached
37
Q

How Is terminal velocity affected when high up in the air?

A
  • at high altitude, the air is thinner
  • meaning a falling object would accelerate for longer periods of time as there’s less air resistance
  • air resistance then increases
  • reaches a higher terminal velocity
38
Q

State Newton’s first law

A

A resultant force is required to change the motion of an object

39
Q

Using Newton’s first law, explain what happens when an object remains stationary

A

If there’s no resultant force acting on a stationary object, the object will remain stationary
The motion won’t change

40
Q

Using Newton’s first law, explain what happens when an object is moving

A

If there’s no resultant force on a moving object, it carries on moving at the same velocity
Motion wont change

41
Q

State Newton’s second law

A

Non-zero resultant forces act on an object, then it will cause the object to accelerate
The size of the resultant force is directly proportional to the acceleration it causes

42
Q

What is inertia?

A

The tendency for the motion of an object to remain unchanged

43
Q

State Newton’s Third law

A

When two objects interact, the forces they exert on each other are equal and opposite

44
Q

What is stopping distance?

A

The minimum distance required to stop a vehicle in an emergency
Stopping distance = Thinking distance + Braking distance

45
Q

What is thinking distance?

A

How far the car travels during the driver’s reaction time

46
Q

What is the thinking distance affected by?

A
  • speed
  • reaction time - linking to being tired, drunk etc.
    All increases reaction time
47
Q

What is braking distance?

A

Distance taken to stop under the braking force

48
Q

What is braking distance affected by?

A

Speed and mass
1. Condition/ quality of the brakes: worn or faulty - wont slow the car as quickly, it’ll travel further before it stops
2. If the road is wet or icy, there’s less friction between the tyres and the road - can cause the car to skid
All increases reaction time

49
Q

What is the conservation of momentum principle?

A

In a closed system, total momentum before = total momentum after

50
Q

Describe what happens to the momentum of people involved in a car crash

A

For the people inside the car, their momentum is going to decrease to 0 almost instantly
They will then experience a huge force which could cause injury

51
Q

How can we reduce the chance of injury when in a car crash and how can it be achieved?

A

You can spread the change in momentum over a longer period of time as it will reduce the force they experience - less likely to get injured
Can be achieved through air bags, seat belts and crumple zones as they all increase the time taken for momentum to be lost - lower force

gcse triple science physics (9 decks)

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