Student Librarian Does Work on Book

[Iceclover]

Homework Statement

a student librarian picks up a 22N book from the floor to a height of 1.25m. He carries the book 8.0m to the stacks and places the book on a shelf that is 1.35m high. How much work does he do on the book

Homework Equations

W=Fd

The Attempt at a Solution

Am i just supposed to add up all the distances and then use my W=Fd formula?

 

[PhanthomJay]

Homework Statement

a student librarian picks up a 22N book from the floor to a height of 1.25m. He carries the book 8.0m to the stacks and places the book on a shelf that is 1.35m high. How much work does he do on the book

Homework Equations

W=Fd

The Attempt at a Solution

Am i just supposed to add up all the distances and then use my W=Fd formula?

Your formula for work is not quite correct. Only the component of the force in the direction of the displacement does work.For example, to find our how much work is done in carrying the book 8.0 meters to the stacks, answer the following question: How much force acts in the direction of the 8 meter displacement?

 

[Iceclover]

what is the correct formula for work then?

 

[PhanthomJay]

what is the correct formula for work then?

$$W = Fdcos\theta$$
where $$\theta$$ is the included angle between the force vector and the displacement vector.