What do we know about forces

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What do we know about forces?
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1. Lets think back!

• When the rocket is moving in space, what happens
  if the engine is turned off? What happens if it
  stays on? How does the rocket stop?
• What does this tell you about the forces on the
  rocket? When are the forces balanced?
• Can you describe when the rocket is moving and
  has balanced forces? Can you describe when the
  rocket is moving and the forces are not balanced?

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2. Parachute Percy

• Think about the forces
  acting on Percy. At what
  points in his story is he
  not moving? What can
  you
  say about the forces
  acting on him at these
  points?
• When is he moving at a steady speed? What can
  you say about the forces at these points?
• When is he accelerating? When is he
  decelerating? What can you say about the forces
  at these points?

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3. Odd one out

• A motorbike doing a steady 60mph on the motorway
• A boy going faster and faster downhill on his
  scooter
• A supermarket trolley moving steadily along the
  aisle
• A supermarket trolley that is not moving.

• Which situation do you think is the odd one out?
  Why have you chosen this one?
• What can you say about the forces in each
  situation? Can you describe if they are balanced
  or not?

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4. Plenary
The forces on a moving object are balanced when .

• How could you complete this sentence?
• What do you know about forces on moving objects?
• What evidence can you think of to support your
  choice of sentence ending?
• Does the whole group agree with the sentence
  ending you have chosen? What is the best ending
  your group can create?