posted by dmkp on .
a ball of mass 200 g is thrown vertically upwards with a velocity of 20ms-1 ignoring air resistance.
a) calculate the kinetic energy of the ball as it is released
b)calculate the maximum height reached by the ball
c) state the velocity of the ball when it returns to its starting position
d)state which conservation principle you used to obtain your answers to questions (b) and (C)
e) if the ball hit the ground 2 metres below the point from which it was thrown, calculate the impulse and impulse force of the 1 millisecond impact.
a. KE = 0.5m*V^2 = 0.1*(20)^2 = 40 Joules.
b. hmax = (V^2-Vo^2) / 2g.
hmax = (0-(20)^2) / -19.6 = 20.41 m.
c. V = Vo = 20 m/s.