1. Who is this? What did he do?

2. Gravity, mass and weight
Success Criteria
Today you will:
Know that gravity is a force
Understand that gravity is different on different planets
Be able to calculate the gravitational field strength on Earth

3. Without gravity…
long)

4. Gravity How do we feel gravity?
We feel gravity as a pull towards the Earth.
The Earth feels the gravitational force of the Sun – this keeps the Earth in orbit around the Sun.
Gravity is an attractive force.
It acts at a distance and the force goes down the further away you go.

6. Gravity and weight

7. Gravity, mass and weight
Success Criteria
Today you will:
Know that gravity is a force
Understand that gravity is different on different planets
Be able to calculate the gravitational field strength on Earth

8. Investigating mass and weight
You are going to do an experiment to see how weight and mass are related to each other. Draw the table in your books:
Mass (kilograms)
Weight (Newtons)

9. Investigating mass and weight
Collected a mass and write the amount of kilograms in the top row of the table.
Use a Newton meter to measure the force due to gravity – the weight. Write this in the weight box underneath the mass.
Mass (kilograms)
Weight (Newtons)

10. Investigating mass and weight
What pattern do you see? What is the connection between mass and weight?
Mass (kilograms)
Weight (Newtons)

11. Investigating mass and weight
Gravitational field strength = weight mass What is the gravitational field strength on Earth? Gravitational field strength = 10 N/kg
Mass (kilograms)
Weight (Newtons)

12. Mass and weight Mass Weight how much “stuff” there is in an object
the force of gravity acting on the mass
Measured in kilograms (kg)
Measured in Newtons (N)

13. Gravity, mass and weight
Success Criteria
Today you will:
Know that gravity is a force
Understand that gravity is different on different planets
Be able to calculate the gravitational field strength on Earth

14. Feeling heavy…
Where would you have the most weight? Would your mass ever change?

15. What happens when a satellite runs out of fuel…?