A block of mass m is suspended vertically with a spring of spring constant k. The block is made to oscillate in a gravitation field. Its time period is fould to be T. Now the space between the plates is made gravity free, and an electric field E is produced in the downward direction. Now the block is given a charge q. the new time period of oscillation is

Options

A. T
B. `T+2 pi sqrt((qE)/(md))`
C. `2 pi sqrt((qE)/(md))`
D. none of the above

Answer

A

Explanation

Time period is independent of a constant force acting on the block of spring-block system. Its time period will remain same as
`T=2 pi sqrt((m)/(k))`.