Question

) a block rests on a rough inclined plane making an angle of 30° with the horizontal. the coefficient of static friction between the block and the plane is 0.8. if the frictional force on the block is 10 n, the mass of the block (in kg) is (take g = 10 m/s2)

Answer 1

here frictional force will be balanced by mgsinr
so f=mgsinr
so m=f/gsinr
=10/5
=2kg