The pulleys and strings shown in the figure are smooth and of negligible mass. For the system to remain in equilibrium, the angle `theta` should be

Options

A. `0^@C `
B. `30^@`
C. `45^@`
D. `60^@`

Answer

C

Explanation

The tension in both strings will be same due to symmetry.

For equilibrium in vertical direction for body B we have
`sqrt2 mg =2T costheta`
`:.` `sqrt2 mg=2(mg) cos theta` [`:' T=mg`, (at euilibrium)]
`:.` `costheta=1/sqrt2impliestheta=45^@`