In the diagram below, points A, B and C lie in the same vertical plane. The slope AB is inclined at an angle of 30° to the horizontal and AB = 5 m. The point B is a vertical distance of 6.5 m above horizontal ground. The point C lies on the horizontal ground.
Starting at A, a particle P, of mass m kg, moves along the slope towards B, under the action of a constant force F. The force F has a magnitude of 50 N and acts at an angle of θ ° to AB in the same vertical plane as A and B. When P reaches B, F is removed, and P moves under gravity landing at C.
It is given that
• the speed of P at A is 3 m s-1,
• the speed of P at B is 6 m s-1,
• the speed of P at C is 12 m s-1,
• 58 J of work is done against non-gravitational resistances as P moves from A to B,
• 42 J of work is done against non-gravitational resistances as P moves from B to C.