P1: Forces

Question 1

All forces are measured in…

Answer 1

Newtons (N)

Question 2

List some examples of contact forces.

Answer 2

Friction

Air resistance

Reaction force

Upthrust

Question 3

What is a force?

Answer 3

A push or a pull

Question 4

The force of water pushing a boat up is called…

Answer 4

upthrust

Question 5

A force that acts without touching is called a…

Answer 5

Non-contact force.

Question 6

What do we use to measure a force?

Answer 6

Newtonmeter (force meter)

Question 7

What 3 effects can forces have on objects?

Answer 7

Change their shape (deform).

Change the direction the object moves in.

Change their speed (accelerate/ decelerate).

Question 8

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

Answer 8

A contact force.

Question 9

List 3 non-contact forces.

Answer 9

Gravity

Magnetism

Electrostatic force

Question 10

Explain how the reaction force works.

Answer 10

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.

Question 11

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

Answer 11

double

Question 12

When a stetched string pulls back we call it…

Answer 12

tension

Question 13

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

Answer 13

reaction force.

Question 14

The amount that a spring can stretch is called its…

Answer 14

extension

Question 15

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…

Answer 15

elastic limit

Question 16

What is the scientific word for ‘squash’?

Answer 16

Compress

Question 17

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

Answer 17

Hooke’s Law

Question 18

Rough surfaces have ______ friction.

Answer 18

more

Question 19

What is friction?

Answer 19

A force that acts when two force against each other.

Friction causes grip.

Question 20

Smooth surfaces have _______ friciton.

Answer 20

less

Question 21

How can you reduce drag forces?

Answer 21

Have a streamlined shape.

Question 22

Name the two drag forces.

Answer 22

Air resistance

Water resistance

Question 23

How can you reduce friction between 2 surfaces?

Answer 23

Use lubrication e.g. oil

Question 24

When is friction a good thing?

Answer 24

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

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

Question 25

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

Answer 25

Weight

Question 26

Why do you weigh less on the moon?

Answer 26

Because the moon has a smaller gravitational field strength.

Question 27

You cannot have weight without…

Answer 27

gravity

Question 28

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

Answer 28

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

Question 29

What is mass?

Answer 29

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

Question 30

Mass is measured in…

Answer 30

Kilograms (Kg)

Question 31

Weight is measured in…

Answer 31

Newtons (N)

Question 32

Is mass a force?

Answer 32

No

Question 33

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

Answer 33

balanced

Question 34

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?

Answer 34

Speed up

Question 35

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

Answer 35

travelling at a constant speed.