Question

If you throw a 0.3 kg ball straight up with an initial speed of 21 m/s, how high will it climb? Round your answer to the nearest tenth and include the appropriate unit.

Answer 1

m = mass = 0.3 kg

v = speed = 21 m/s

g= gravity =9.8 m/s^2

h= height

Conservation of mass:

Potential energy = Kinetic energy

1/2 m v^2 = m g h

Replacing:

1/2 (0.3 ) (21)^2 = (0.3) (9.8) h

Solve for h

66.15 = 2.94h

66.15/2.94 = h

h = 22.5 m