Question

A `2 kg` block moving with `10m//s` strikes a spring of constant `pi^(2)N//m` attached to `2Kg` block at rest kept on a smooth floor. The time for which rear moving block remain in contact with spring will be-

A. `sqrt(2)` sec
B. `(1)/(sqrt(2))` sec
C. 1 sec
D. 1/2 sec

Answer 1

Correct Answer - C
`T=2pisqrt((mu)/(k))`
`T=(2pi)/(pi)impliesT=2sec`
Required time `=(T)/(4)+(T)/(4)=(T)/(2)=1sec`.