Question
Two bodies of masses m1 and m2 are connected by a light string passing over a smooth light pulley fixed at the end of an inclined plane. The mass m1 is hanging and mass m2 lies on inclined plane in equilibrium. Find the angle of inclination of inclined plane.
Solution
The system is in equilibrium, therefore the acceleration of the system of masses is zero.
∴
Equation of motion for mass m1,
...(1)
Equation of motion for mass m2,
...(2)
From (1) and (2),
, is the required angle of inclination of inclined plane.
∴
Equation of motion for mass m1,
...(1) Equation of motion for mass m2,
...(2) From (1) and (2),
, is the required angle of inclination of inclined plane. 
