(A) : A block of mass .m. rests on a wedge of mass M, which, in turn, is at rest on a horizontal table. All the surfaces are friction less. The block starts from rest. The position of c.m of the system will change only in vertical direction.
(R ) : A block of mass .m. rests on a wedge of mass M, which, in turn, is at rest on a horizontal table. All the surfaces are friction less. The system is free from external force along horizontal direction.

Options

A. Both (A) and (R ) are true and (R ) is the correct explanation of (A)
B. Both (A) and (R ) are true and (R ) is not the correct explanation of (A)
C. (A) is true but (R ) is false
D. Both (A) and (R ) are false

Answer

A