Question

A block is kept on smooth inclined plane of angle of inclination 30 degree that moves with a constant acceleration so that the blog does not slide relative to the incline plane let F1 be the contact force between the block and the plane now the inclined plane stop and let F2 be the contact force between the two in this case. then f/f2 is

Answer 1

The net force acting on the block is zero as it is traveling with constant velocity. Therfore, the fractional force acting on the block is equal and opposite to the gravitational force on the block. The gravitational force would be mg(sin30) where m is the mass and g is the acceleration due to gravity. Frictional force is given by the product of coefficient of dynamic friction and normal force acting on the block. Normal force acting on the block would be mg(cos30). Therfore, coefficient of dynamic friction is given by mgsin30/mgcos30 which is equal to tan30 i.e 1/√3.