## Exercise 3.8 A

Compare the amount of work done when lifting or pulling a piece on a sloping level to height h.

Answer: It is noticed that the work on the sloping level to height h is slightly larger than the lifting work at the same height. The reason is the friction between the substrate and the body. In this work, the friction force is low (the piece is pulled by wheels) but it is noticeable. If there was no friction force, the work would be the same. The table clearly shows that doing the same work with less force will cause the distance to extend.

## Exercise 3.8 B

Determine the work done by the force.

Answer: $1{,}3 \ J$

## Exercise 3.8 C

Specify the amount of power to the move of the body.

Answer: $0{,}15 \ W$