Question

A metal sphere is hung by a string fixed to a wall. The sphere is pushed away from the wall by a stick. The forces acting on the sphere are shown in the second diagram. Which of the following statements is wrong?

A. `P=W tan theta`
B. `vec(T)+vec(P)+vec(W)=0`
C. `T^(2)=P^(2)+W^(2)`
D. `T=P+W`

Answer 1

Correct Answer - D

As the metal sphere is in equilibrium under the effect of three forces therfore `vec(T)+vec(P)+vec(W)=0`
From the figure `T cos theta=W`….(i)
`T sin theta=P`….(ii)
From equations (i) and (ii), we get
`P=W tan theta`
and `T^(2)=P^(2)+W^(2)`