What is the velocity of the bob of a simple pendulum at its mean position, if it is able to rise to vertical height of 10 cm (take `g=9.8m//s^(2)`)

Options

A. 0.6 m/s
B. 1.4 m/s
C. 2.2 m/s
D. 1.8 m/s

Answer

B

Explanation

For the bob of a simple pendulum, oscillating in a vertical plane, P.E. at the highest point = K.E. at the lowest point (mean position)
`mgh=(1)/(2)mv^(2)`
`therefore v^(2)=2gh or v=sqrt(2gh)=sqrt(2xx9.8xx0.1)`
`therefore v=sqrt(1.96)=1.4 m//s`