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A child pushes horizontally on a box of mass m which moves with constant speed v across a horizontal floor. The coefficient of friction between the box and the floor is µ. At what rate does the child do work on the box?

User Tbsalling
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1 Answer

3 votes

Answer:

Step-by-step explanation:

mas of box = m

velocity = v

coefficient of friction = μ

Force = coefficient of friction x Normal reaction

F = μmg

rate of doing work is called power, so

P = Force x velocity

P = F x v

P = μmg x v

P = μmgv

User Shyam Kansagra
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