Forces 1

Forces

Engage in interactive activities to understand the concept of forces and their effects. Discover the principles of physics through hands-on experiments and games. Get ready for a fun-filled exploration of the world of forces!

Think - Pair - Share "Jar roll"

• How can we make the jar roll further without changing the ramp?

• What if the ramp was covered with a different material?

• What if the jar was bigger or smaller?

• What if the jar was half full of water?

9.1 A force is a push, a pull or a twist

Learning intentions:

•To learn that a force is a push or pull that happens when two objects interact

•To learn that the effect of forces can be measured

•To learn that gravity affects the movement of objects on Earth

Open Ended

What can forces do to objects?
(Brainstorm with the person sitting next to you.)

Forces cause objects to:

• Begin to move

• Speed up

• Slow down or stop

• Change direction

• Change shape

• Spin

• Remain still

Usually more than one force is acting on objects at any one time…

Multiple Choice

What force causes objects to be pulled towards the Earth?

• Friction

• Magnetism

• Gravity

• Buoyancy

Gravity

Did you know? Gravity is the force that keeps us grounded on Earth. It is what makes objects fall towards the ground. Without gravity, we would float away! Fun fact: Gravity is also responsible for keeping the planets in our solar system orbiting around the sun.

• 2 or more forces that are unequal in size and direction can cause change in an object’s speed, direction or shape

An unbalanced force causes change

• We can use scales in our kitchen to measure the force of gravity (20 g of flour pushes down on the scales)

• In a lab, we use a spring balance to measure force

• A rubber band can be used in the same way to measure force

• Before we can use a rubber band to measure force it must be calibrated ( we match the stretch of the rubber band to the force pulling on it)

Measuring forces

Measuring Forces

• Use scales or spring balances to measure forces
• Calibrate a rubber band to measure force
• Forces are measured in newtons (N)
• 100g being pulled towards the center of the Earth is 1 N

• Named after Sir Isaac Newton who first described the force used to pull an apple from a tree)

• Spring balances are sometimes called newton meters

• Scientists agree that the force of 100g being pulled centre of Earth is 1 N.

​We measure forces in units called NEWTONS (N)

Multiple Choice

What unit is used to measure forces?

• Grams

• Kilograms

• Pounds

• Newtons

• ​Contact force occur as a result of two objects making contact with each other

Contact force

• •Non-contact forces occur when one object is able to push or pull another without touching the other

Non-contact force