The correct option is
A −[4m1m2+m0(m1−m2]g4m1m2+m0(m1+m2)Here refer to the fig. for the scheme of the motion of the system
Let the tension in the lower string be T
Therefore tension in the upper string is 2T
Also let acceleration of both the mass M1andM2 w.r.t. the lower pulley be a1
Also let the acceleration of lower pulley w.r.t. ground=a
So, acceleration of masses M1andM2 w.r.t. ground is a1−aanda1+arespectively
So, the three equations of motion for masses M0,M1,M2respectivelyare,2T=M0a0⟶(equation1)T−M1g=M1(a1−a0)⟶(equation2)M2g−T=M2(a1+a0)⟶(equation3)
Solving the three equations we have a1−a0=−[4m1m2+m0(m1−m2)]g4m1m2+m0(m1+m2)