Forces

Forces

Forces

Objects cannot move on their own

Forces must be applied like the the shapes in the image.

What is a force?

A force is a push and pull

Look at the picture for what a push and pull force is

What is a force?

A force is a push and pull

Look at the picture for what a push and pull force is

Which requires more force?

If something is light do you need much force?

If something is heavy do you need much force?

Difference between small and large force

If you were to close a door.

What happens when you use a small force?

What happens when you use a large force?

Friction Force

What is friction?

Friction is when one object rubs against another material.

Look at the picture see how the detail of the crate and carpet, will it be hard or easy to push?

What is friction?

Friction is the force that goes opposite to your pushing force.

This also applies when you pull.

Exercise

If you're pushing a big rock which will be easier? pushing on earth? or pushing on ice?

Exercise

Pushing it on ice would be easier since its smooth there is less friction.

Pushing on earth is rough making it harder to push.

Balanced Forces

What does 'balance' mean?

Balanced Forces

Balanced forces are when two opposite forces are equal to each other.

Look at the boy he is able to carry without difficulty.

Balanced Forces

The bag and the boy's shoulders have opposite and equal force.

Balanced Forces

Your weight is also a force, the reason you're able to stand on earth is because the earth is pushing the same force back to you.

Unbalanced Forces

What do you think 'unbalance' means?

Unbalanced Forces

Unbalanced forces are when one of the force(s) is greater than the other.

Unbalanced Forces

Its not usually one force that does, it can be many forces that have an overall effect.

Unbalanced Forces

You can see a number of dogs pulling the sled as there is a greater force to the sled and man.

Multiple Select

What is a force?

Select all that apply.

• push

• pull

• strength

• light

Multiple Choice

What is friction?

• when objects rub each other

• when objects don't rub each other

• when objects fight

Multiple Choice

Determine if friction is high or less.

Pushing the sofa on carpet

• high

• less

Multiple Choice

Determine if friction is high or less.

Pushing sled on snow

• high

• less

Multiple Choice

Determine if friction is high or less.

Going down on a slide

• high

• less

Multiple Choice

Determine if friction is high or less.

Pulling small boat on water

• high

• less

Multiple Choice

Determine if its balanced or unbalanced forces.

Sitting on a chair

• balanced

• unbalanced

Multiple Choice

Determine if its balanced or unbalanced forces.

2 people vs 5 people pulling rope.

• balanced

• unbalanced

Multiple Choice

Determine if its balanced or unbalanced forces.

pushing your bag along the table

• balanced

• unbalanced

Multiple Choice

Determine if its balanced or unbalanced forces.

a computer sitting on your table

• balanced

• unbalanced

Multiple Select

How do forces change the motion of objects?

Select all that apply

• Forces can change the speed or direction of an

  object’s motion.

• The size of the force affects the speed of the object.

• The direction of the force affects the direction of

  the object’s motion.

Multiple Choice

An egg is about to roll off the counter. How can you get the egg to stop without picking it up?

• you must pick it up

• apply a force in the opposite direction

• catch it as its about to fall

Multiple Choice

If an object is rolled on a high friction surface, will the object go far?

• yes

• no