A constant force of 20 N is applied to an object of mass 8.0 kg at an angle of 25° with the horizontal. What is the work done by this force on the object if it causes a displacement of 2.0 m along the horizontal direction?
A) 40 J
B) 0 J
C) 36 J
D) 17 J
E) 19 J

Question

Quizplus · Accepted Answer

The horizontal component of the applied force (20 N) is given by:
Fh = F cosθ = (20 N) cos(25°) ≈ 18.2 N

The work done by this horizontal force on the object is given by:
W = Fh d cosφ, where d is the displacement along the horizontal direction and φ is the angle between the force and the displacement.

Since the force and the displacement are both along the horizontal direction, we have φ = 0, so cosφ = 1.

Substituting the values, we get:
W = (18.2 N)(2.0 m)(1) = 36.4 J ≈ 36 J

Therefore, the answer is (C) 36 J.

A Constant Force of 20 N Is Applied to an Object