Question

Susan is standing on the edge of the Grand Canyon with a tennis ball of mass 0.06 at rest. Once she lets it go, if falls a distance of 1237 meters. How fast is the ball traveling the split second before it hits the ground? Gravity is 9.8 m/s² Round answer to the nearest meter per second.

Answer 1

Potential energy (PE) = m g h

Kinetic energy (KE ) =1/2 m v^2

Where:

m = mass = 0.06 kg

g = acceleration of gravity = 9.8 m/s^2

h = heigth = 1237 meters

v= speed

PE = 0.06 * 9.8 * 1237 = 727.356 J

PE = KE

727.356J = 1/2* 0.06 * v^2

Solve for v

727.356 J / ( 1/2 * 0.06 ) = v^2

24,245.2 = v^2

√24,245.2 = v

v = 156 m/s