The work done on the block by the gravitational force during the 5-meter slide down the plane is most nearly

Question

A plane 5 meters in length is inclined at an angle of 37°, as shown. A block of weight 20 newtons is placed at the top of the plane and allowed to slide down.

The work done on the block by the gravitational force during the 5-meter slide down the plane is most nearly 

(A) 20 J 

(B) 60 J 

(C) 80 J 

(D) 100 J 

(E) 130 J 

Answer 1

Correct option (B) 60J

As the box slides down the incline, the gravity force is parallel to the height of the incline the whole time so when finding the work or gravity you use the gravity force for F and the height of the incline as the parallel distance. Work = (F_g)(d) = (20)(3).