Using the equation of motion,
v^2 = u^2 + 2as, where v = final velocity, u = initial velocity = 0 m/s, a = acceleration = gravitational acceleration = 9.81 m/s^2, s= distance = 50 m
Therefore,
v = Sqrt (2*9.81*50) = 31.32 m/s
But, it is noted that the actual velocity is 26 m/s.
The difference between Kinetic Energies is the work done to overcome the air resistance.
That is,
Work done = 1/2*10*31.31^2 - 1/2*10*26^2 = 1/2*10 (31.32^2-26^2) = 1,525 J
