Suppose I push a block along a tabletop at a constant velocity. If I exert a constant forward force of on the block and push it through a distance D, I do work on the block equal to ?F?D. Since the block’s kinetic energy does not change, friction must be exerting a backward force on the block of the same magnitude as (so that the net force on the block is zero, as required to maintain the block’s constant velocity). What work does the friction force do on the block?

A. No work

B. ? D

C. + D

D. Some negative work, but we need more information to determine exactly how much.

E. Some positive work, but we need more information to determine exactly how much.




D. Some negative work, but we need more information to determine exactly how much.

Physics & Space Science

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Physics & Space Science

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Indicate whether the statement is true or false

Physics & Space Science