Question

an object of mass 50 kg is raised to height of 4m above the ground what is the potential energy ? if the object is allowed to fall, what is kinetic energy when its half way down ​

Answer 1

Potential energy =mgh

=50×4×9.8

=1960J

Answer 2

Potential energy =mgh

m=50 kg

g=10 m/s^2

h=4 m

Therefore,

           Potential energy=50x4x10

           Potential energy=2000 Joules

From conservation of energy,

   Change in Potential energy= Change in Kinetic energy

    At the top most point, velocity is zero, hence Kinetic energy (1/2 xmxv^2) is also zero.

    50x10x4 - 50x10x2= K.E

    K.E.(halfway down) = 1000 Joules.

Hope this helps.

Good luck!