JAMB Physics 1990 Question 8

Question 8

Equilibrium of Forces

A force of 5 N acts at a point Y on a rod XYZ as shown in the diagram above. If XY is 2 m, what is the moment of the force about point X?

Diagram for this question
  1. A.0 N m
  2. B.3 N m
  3. C.7 N m
  4. D.10 N m
Show the answer and explanation

Answer: A (0 N m)

Explanation

The force acts along the rod itself, so its line of action passes through X. The perpendicular distance is zero and so is the moment.