question_answer

Two bodies of masses 1 kg and 4 kg are connected to a vertical spring, as shown in the figure. The smaller mass executes simple harmonic motion of angular frequency 25rad/s, and amplitude 1.6 cm while the bigger mass remains stationary on the ground. The maximum force exerted by the system on the floor is (take \[g=10m{{s}^{-2}}\])     [JEE ONLINE 09-04-2014]

A)  20 N   

B)       10 N

C)  60 N   

D)       40 N

Correct Answer: C

Solution :

[c] Mass of bigger body M = 4 kg

Mass of smaller body m = 1 kg

Smaller mass (m = 1 kg) executes S.H.M of angular frequency rad/s

Amplitude

As we know,or

or

or

The maximum force exerted by the system on the floor