The mass of the bob of a conical pendulum is 100 g and the length of the string is 150 cm . If the radius of the circle in which the bob rotates is 22 cm and if the thread makes an angle of `15^(@)` with the vertical , calculate the velocity of the bob.

Options

A. `0.76` m/s
B. `0.84` m/s
C. `1.2` m/s
D. `2.4` m/s

Answer

A

Explanation

`tan theta =(v^(2))/(rg)`
`(OA)/(mg) =(AB)/((mv^(2))/r)=(OB)/T`
`tan theta = (AB)/(OA) =(mv^(2))/(rmg) =(v^(2))/(rg)`
`tan 15 =(v^(2))/(0.22 xx 9.8)`
`v = sqrt(0.22 xx 9.8 xx tan 15 ) = 0.76 ` m/s