A pulley block and tackle is used to lift a piano. The piano weighs 2000N. If the worker used 100 N of force to lift the piano, what is the mechanical advantage of the block and tackle?

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Weight of a man is less at coal mine. Why?

Find the displacement if the velocity is 100 km to the east, time=3 h

Which property will eventually be the same for two objects after thermal energy is transferred btween them

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