A ring of mass 5 kg sliding on a frictionless vertical rod connected by a clock B of mass 10 kg by the help of a massless string.
Then, at the equilibrium of the system, the value of `theta` is

Options

A. `30^(@)`
B. `60^(@)`
C. `90^(@)`
D. `0^(@)`

Answer

B

Explanation

For ring,
From force diagram of ring,
`T cos theta = m_(1)g " "...(i)`
For block B,
mg = T
`T cos theta = m_(1) g`
`mg cos theta = m_(1)g`
`therefore " "cos theta=(m_(1))/(m)=(5)/(10)=(1)/(2)`
`implies " "theta=60^(@)`