Question

earning Goal: To be able to calculate work done by a constant force directed at different angles relative to displacement

If an object undergoes displacement while being acted upon by a force (or several forces), it is said that work is being done on the object. If the object is moving in a straight line and the displacement and the force are known, the work done by the force can be calculated as
W= F*s=/F/ /s/ cosθ
,

where W is the work done by force F on the object that undergoes displacement s directed at angle θ relative to F .

Note that depending on the value of cosθ, the work done can be positive, negative, or zero.

In this problem, you will practice calculating work done on an object moving in a straight line. The first series of questions is related to the accompanying figure. (Intro 1 figure)








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Question= Find the work W done by the 30-newton force.

Use two significant figures in your answer. Express your answer in joules.

Answer 1

Answer:

the work done by the 30N force is 4156.92 J.

For this problem, they don´t ask you to determine the work of the total force applied in the block. They only want the work done for the force of 30N, with an angle of 30º respectively of the displacement and a traveled distance of 160m. So:

W=F·s·cos(α)=30N·160m·cos(30º)=4156.92J