How Things Work

How Things Work How Things Work A wheel and a lever are simple machines. A pulley and a ramp are simple machines. Machines can be different. Machines can help us go places. Machines can help us do work. Parts make a bicycle move.

Aug 18, 2021 - 12:51
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How Things Work



How Things Work

A wheel and a lever are simple machines.

A pulley and a ramp are simple machines.

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