Question

Work on a sliding crate.

A worker pushes a 47.0 Kg crate across a level horizontal floor by applying a constant force of exactly 150.0 N at an angle of 23.0 degrees below the horizontal. The crate begins at rest and ends 15.0m from where it started traveling at 2.6m/s

A. What is the work done by the applied force as the crate moves across the floor?

B What is the work done by the friction force as the crate moves across the floor?

C. What is the coefficient of kinetic friction [Uk] between the crate and the horizontal plane?

Answer 1

We know the equation of motion,

.......................(4)

Where, v is final velocity

u is initial velocity

a is acceleration of the object

S is total displacement

For the crate

v = 2.6 m/s

u = 0 m/s

S = 15 m

So,

  

or,  

Workdone by a force(F) is given by

.................(5)

Where, S is displacement

(A) Workdone by applied force is

(B) From equation (1),

or,

or,

Work done by force of friction is

  

(C) From equation (3),

or,   

or,

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