Question

5. A particle moves under the action of a force F = 20i +15 jalong a straight line 3y + ax = 5 where a is a
constant. If the work done by the force F is zero, then the value of a is
4/9
9/4
3
4



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Answer 1

Answer:

Work done = Force *displacement

W=0 , if F=0

             x=0

or if force is perpendicular to displacement

cos 90=0