Balanced & unbalanced forces

WALT: To calculate the resultant force acting on an object

1st task… Name THREE forces and describe the effect of each force

By the end of the lesson we…

Must…Describe the effect of different forcesShould…Explain the term ‘balanced forces’Could…Explain the term ‘unbalanced forces’Calculate the resultant force

Balanced and unbalanced forces

• If two forces are acting on an object in opposite directions, the object will move in the direction of the larger force.

• If the two forces are the same size but in opposite directions, they balance out. These forces are called balanced forces.

Video Clip

50 Newtons 30 Newtons 16 Newtons

25 Newtons

300 Newtons

100 Newtons

Unbalanced Forces

Balanced Forces

Balanced & unbalanced forces

• Pushes and _________ are forces.

• The force of gravity pulling towards the Earth is called ___________.

• An object placed in water has a force called ________ pushing up on it.

• When the forces acting on an object are equal and opposite, they are called ___________ ______.

• If the forces are balanced, the object will stay still or carry on at the same speed in the same direction.

Quick Re-cap

Switch on your Qwizdom handsets

If two different forces are acting on an object in opposite directions,

the object will:

A) Stay in the same placeB) Move in the direction of the larger

forceC) Move in the direction of the weaker

force

Enter the correct answer

• The forces on a person are _________

Choose all that apply....If the forces are balanced an object will:

A) Stay stillB) Slow downC) Carry on at same speed in the same

direction

Forces posterYour task…

Produce a poster about what you have learnt so far about forces

Level 3: Explain what forces are

Give meanings and examples of forces, draw a force diagram e.g. of a fish

Level 4: Explain balanced & unbalanced forces

Explain what happens in a tug of war. How does a car keep at a steady speed? Draw force diagrams to help explain both

Level 5: Explain what density is & how it is measured

Draw a force diagram showing the forces acting on an object in water

HOMEWORK