Two identical blocks `P` and `Q` have mass `m` each. They are attached to two identical springs initially unstretched. Now the left spring (along with `P)` is compressed by `A//2` and the right spring (along with `Q`) is compressed by `A`. Both the blocks are released simultaneously. They collide perfectly inelastically. Initially time period of both the blocks was `T`.

The time period of oscillation of combined mass is

Options

A. `(T)/(sqrt(2))`
B. `sqrt(2)T`
C. `T`
D. `(T)/(2)`

Answer

C

Explanation

They will collide at their positions because time period of both are same and that is `2pi sqrt((m)/(k))`. After collision combined mass is `2m` and `K_(eff) =2K`. Hence, time period remains unchanged.