The correct option is
A m2g(4m1+m2)When the block
m2 moves downward with acceleration a, the acceleration of mass
m1 will be 2a because it covers double distance in the same time in comparison to
m2.
Let T is the tension in the string.
By drawing the free body diagram of A and B
T=m1 2a−−−−−−−−−−(i)
M2g−2T=m2a−−−−−−−−−−−(ii)
By solving (i) and (ii)
By solving (i) and (ii)
a=m2g(4m1+m2)