Question Detail
Question
A force F pulls a block a distance s along a horizontal surface at an angle θ above the horizontal. What is the correct expression for the work done by the force F?
Correct Answer
Option C is the correct answer.
Detailed Explanation
The work done by a constant force is the product of the displacement and the component of the force parallel to the displacement. The component of F parallel to the horizontal displacement is F cos θ. Therefore, the work done is W = (F cos θ) × s = F s cos θ.
Hint
Only the component of the force that acts in the direction of the motion does work.