What is the correct kinetic energy in the following case?We dropped a golf ball from 50 cm above the ground into a sand pit. It took 0.046 seconds...

When a ball is falling under gravity, there is a force
acting on it due to the gravitational pull of the Earth. This force accelerates the ball
as it falls down.

In calculating the kinetic energy of the
ball when it hits the sand pit, you require the velocity(or speed) of the ball when it
has dropped down 50 cm. This cannot be calculated using the formula s = d/t as
that formula is valid only for a body moving at a constant speed, not if the body is
under acceleration.

If the kinetic energy has to
be calculated we need the mass of the ball in addition to its velocity. That also has
not been provided.

You can calculate the
final velocity of the ball as (2*0.5/0.46)
m/s

This velocity can get be
substituted into the expression for kinetic energy to calculate
it.