Three blocks A, B and C are lying on a smooth horizontal surface, as shown in the figure. A and B have equal masses, m while C has mass M. Block A is given an inita speed v towards B due to which it collides with B perfectly inelastically. The combined mass collides with C, also perfectly inelastically `(5)/(6)th` of the initial kinetic energy is lost in whole process. What is balue of M/m?

Options

A. 2
B. 5
C. 3
D. 4

Answer

D

Explanation

P = Constant = mv , Loss in KE = 5/6 th of `KE_i`
`implies KE_f = 1/6 th "of" KE_i " "implies " " (P^2)/(2(M + 2m)) = 1/6(P^2)/(2m)`
`implies M + 2m = 6m " " implies " " M = 4m`.