In the arrangement shown in the fig. the pulley, the spring and the thread are ideal. The spring is stretched and the two blocks are in contact with a horizontal platform P. When the platform is gradually moved up by 2 cm the tension in the string becomes zero. If the platform is gradually moved down by 2 cm from its original position one of the blocks lose contact with the platform. Given M = 4 kg, m = 2 kg.
(a) Find the force constant (k) of the spring
(b) If the platform continues to move down after one of the blocks loses contact, will the other block also lose contact? Assume that that the platform moves very slowly.

Answer

(a) K = 2.5 N/cm
No