Luke's dad built a seesaw using a long plank and a saw-horse. Luke's father stood at his end and pushed the seesaw up and down. He tried two different ways of doing this as shown in the diagrams.
| Diagram A | Diagram B |
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| a) |
Draw an arrow pointing to the position of the pivot (fulcrum) on Diagram A. |
| b) |
In which diagram does Luke's dad need to use less force to lift the seesaw? ___________ |
| c) |
Luke and his father were sitting balanced on the see-saw. Luke's mass was 30 kg and he was sitting 2 metres away from the saw-horse. Luke's father had a mass of 60 kg. How far away from the saw-horse was his father sitting? [NOTE: mass 1 × distance 1 = mass 2 × distance 2] ________________________________________________________________________ |