A block of mass `m` is at rest on an another block of same mass as shown in figure lower block is attached to the spring than the maximum amplitude of motion so that both the block will remain in contact is

Options

A. `(mg)/(2k)`
B. `(mg)/(k)`
C. `(2mg)/(k)`
D. `(3mg)/(2k)`

Answer

C

Explanation

The block will remain in contact till the block do not go above the netural length of the spring because after this condition of lower block becomes more then upper block due spring force so they will get separated
So maximum position amplitude `= x_(0) = (2mg)/(k)`