P1: Forces Flashcards

1
Q

All forces are measure in…

A

Newtons (N)

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

List some examples of contact forces.

A

Friction

Air resistance

Reaction force

Upthrust

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

What is a force?

A

A push or a pull

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

The force of water pushing a boat up is called…

A

upthrust

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

A force that acts without touching is called a…

A

Non-contact force.

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

What do we use to measure a force?

A

Newtonmeter (force meter)

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

What 3 effects can forces have on objects?

A

Change their shape (deform).

Change the direction the object moves in.

Change their speed (accelerate/ decelerate).

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

What do we call forces that act when you touch something?

A

A contact force.

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

List 3 non-contact forces.

A

Gravity

Magnetism

Electrostatic force

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

Explain how the reaction force works.

A
  1. The floor is a solid and made from particles.
  2. Your weight pushed the particles together.
  3. The bonds holding the particles together are compressed.
  4. They push back to support you.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

If you double the force on a spring you will _________ the extension (stretch) of the spring.

A

double

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

When a stetched string pulls back we call it…

A

tension

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

The force of the Earth pushing an upject up is called the…

A

reaction force.

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

The amount that a spring can stretch is called its…

A

extension

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

If you stretch a spring so long that it can no longer go back to its original size we say that the spring has reached its…

A

elastic limit

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

What is the scientific word for ‘squash’?

A

Compress

17
Q

“The stretch of a spring is diectly proportional to the force applied, providing the elastic limit has not been reached”. This is called …….

A

Hooke’s Law

18
Q

Rough surfaces have ______ friction.

A

more

19
Q

What is friction?

A

A force that acts when two force against each other.

Friction causes grip.

20
Q

Smooth surfaces have _______ friciton.

A

less

21
Q

How can you reduce drag forces?

A

Have a streamlined shape.

22
Q

Name the two drag forces.

A

Air resistance

Water resistance

23
Q

How can you reduce friction between 2 surfaces?

A

Use lubrication e.g. oil

24
Q

When is friction a good thing?

A

Friction between your shoe and road to allow you to walk.

Friction between bike/car brakes and the wheels to allow you to stop.

25
Q

The force of gravity acting on an object (with a mass) is called…..

A

Weight

26
Q

Why do you weigh less on the moon?

A

Because the moon has a smaller gravitational field strength.

27
Q

You cannot have weight without…

A

gravity

28
Q

What is the equation for calculating weight on any planet/moon?

A

Weight (N) = Mass (Kg) x Gravitational Field Strength (N/Kg)

29
Q

What is mass?

A

The amount of ‘stuff’ that an object is made from.

30
Q

Mass is measured in…

A

Kilograms (Kg)

31
Q

Weight is measured in…

A

Newtons (N)

32
Q

Is mass a force?

A

No

33
Q

When forces acting on an object are the same size in opposite directions we say that they are…

A

balanced

34
Q

If the engine force of a car is greater than the air resistance acting on it will the car speed up, slow down or travel at the same speed?

A

Speed up

35
Q

If the downward force of a parachutist due to gravity is equal to the upward force due to air resistance, the parachutist will be………

A

travelling at a constant speed.