Year Seven Science Forces

Front 1

What is a force?

Back 1

A push, pull or twist.

Front 2

List some things forces can do?

Back 2

Start an object moving

Speed an object up

Cause an object to change direction
Change the shape of something

Stop or slow and object

Front 3

These are examples of what kind of instrument used for measuring forces?

Back 3

Springbalance

The larger the pulling force, the more the spring is stretched and the higher the reading on the scale.

Front 4

The forces acting on this bike are _________?

Back 4

Balanced (Doesn't always mean an object is stopped. It could be travelling at a constant speed.)

Front 5

The forces acting on this bike are_________ ?

Back 5

Unbalanced

When forces become unbalanced, the motion of the object will change.

Front 6

What is inertia?

Back 6

The tendency of any object to resist any change in its motion (stay still).

Front 7

True or false?
The bigger something is, the greater its inertia.

Back 7

True - E.g. It takes a smaller force to stop a pebble rolling than a boulder.

Front 8

What is friction?

Back 8

The force that slows things down. Friction occurs whenever two objects are in contact.

Front 9

Explain Newton's 1st Law?

Back 9

Objects that are moving, will continue to do so unless a force acts on them.

Front 10

Give some examples of why friction is important?

Back 10

It slows things down, stops them and provides grip.
Provides grip needed by cars and bikes on the road, otherwise the wheels would spin and the car wouldn't go anywhere.
Helps us walk.
Helps you to change direction and slow down.

Front 11

True or false?
Even 'smooth' surfaces, like glass, have bumps on them that create friction.

Back 11

True

Front 12

What two things affect friction?

Back 12

1) How rough the surfaces in contact are
2) How hard the surfaces are pushed together.

Front 13

Give some examples of unwanted friction.

Back 13

Friction causes heat - makes machines less efficient/wastes energy.

Front 14

List some ways to reduce friction.

Back 14

Oiling or lubricating a machine to reduce friction.
Reducing the weight reduces friction (eg. taking books off a bookshelf before moving it).

Front 15

What is gravity?

Back 15

All objects attract each other. This force of attraction is called gravity.

Front 16

What is mass?

Back 16

The amount of matter in an object (its size).

Front 17

What is weight?

Back 17

The name given to the pulling force of gravity on an object. Your weight depends on your mass and the strength of the gravitational field of the planet you are on.

Front 18

List things that may affect the stability of a structure.

Back 18

Wind

Rain
Hail

Extreme heat
Extreme cold

Front 19

True or false?
Galileo discovered that the more something weighed, the faster it falls.

Back 19

False
Galileo discovered things fall faster because they have smaller surface areas (less air resistance), not because they weighed more.

Front 20

What is terminal velocity?

Back 20

When the forces acting on an object are balanced and the object falls at a constant speed it has reached it's terminal velocity.