A worker pushed a 27kg block 9.2m along a level floor at constant speed with a force directed 32* below the horizontal. If the coefficient of kinetic friction between block and floor was 0.20, what were (a) the work done by the worker's force and (b) the increase in thermal energy of the block-floor system?

Question

souvik · Answer

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word done by the worker=$\vec{F}.\vec{s}$
and the increase in thermal energy of the block-floor system=the work done by friction