Physics
Richa weighing 40 kgf leaves point P on her skateboard and reaches point Q on the ground with velocity 10 ms-1. Calculate.

(a) the kinetic energy of Richa at point Q
(b) the vertical height of point P above the ground. (use g as 10 m/s2 and neglect friction)
(c) the kinetic energy of Richa at point R. (While moving from Q to R, she loses 500 J of energy against friction.)
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