Two blocks lie on each other and connected to a spring as shown in figure. What should be the mass of blocks A placed on block B of mass 6 kg, so that the system's period is 0.75 s ? Assume no slipping, what should be the minimum value of coefficient of static friction `mu_(s)` for which block A will not slip relative to block B, if block B is displaced 50 mm from equilibrium position and released ?

Options

A. 2 kg, `mu_(s)` = 0.4
B. 4.2 kg, `mu_(s)` = 0.358
C. 2.56 kg, `mu_(s) ge` 0.358
D. 2.56 kg, `mu_(s) le` 0.358

Answer

C

Explanation

`T = 2pi sqrt((m_(1) + m_(2))/(k)) and mu = (A omega^(2))/(g)`