Question

Calculate the work done in pushing a wooden block through the distance of 4.5m against the force of friction is 200N . Also write the type of work

Answer 1

Work=Force×distance
work=200×4.5
work=900NM.
It is negative work.

Answer 2

 Work , W = Force (F)  × Displacement (s)
     
Force =  - 200 N ( the force is negative because it is acting against the displacement)

s = 4.5 m

W  = - 200  × 4.5
     = - 900 J

The work done is negative.