(A) : A disc released from the top of a fixed inclined plane rolls down without slipping if the inclined plane is rough only
(R ) : Friction does no work in pure rolling

Options

A. Both 'A' and 'R' and true and 'R' is the correct explantation of 'A'
B. Both 'A' and 'R' and true and 'R' is not the correct explantation of 'A'
C. A' is true and 'R' is false
D. A' is false and 'R' is true

Answer

B