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How can a pulley make lifting easier without saving energy?

A pulley arrangement can reduce the force needed to raise a load by increasing how far the rope must move. In an ideal system the work balances, while friction adds losses to real machinery.

4–5 min

Questions you could explore

  • How does a fixed pulley differ from a moving one?
  • Where does the distance trade-off appear?

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Why metal can feel colder than wood

Physics5–7 minA metal handle and a wooden tabletop can share a room temperature yet feel quite different. The clue lies in the exchange of heat between your hand and the surface, which is not the same thing as measuring temperature.

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3–5 min

How can a ship made of steel float?

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