Statement I: A block of mass m starts moving on a rough horizontal surface with a velocity v. It stops due to friction between the block and the surface after moving a certain distance. The surface is now tilted to an angle of 30∘ with the horizontal, and the same block is made to go up on the surface with the same initial velocity v. The decrease in the mechanical energy in the second situation is smaller than that in the first situation.
Statement II: The coefficient of friction between the block and the surface decreases with the increase in the angle of inclination.
If statement I is true, Statement II is false
Statement I is true. When the block is made to go up the inclined plane, some part of the mechanical energy is converted into gravitational potential energy. Hence, the decrease in mechanical energy is smaller.
Statement II is false. The coefficient of friction doesn't depend on the angle of inclination of the plane.