Question

Solve the Following.

1. Calculate the kinetic energy of a ball of mass 100g going with a speed of 20 m/s.

2. A stone of mass 500g is raised from a height of 2m to 4m. Find the change in its

potential energy.
with working pls​

Answer 1

Explanation:

Kinetic Energy, K.E=0.5×m×v2

K.E=0.5×0.5×15×15=56.25J

As it has 56.25 J at the initial point as total energy, at some point X,Potential Energy(P.E.) is maximum.

Total energy=P.E.+K.E.

56.25=P.E.+K.E.

As energy is conserved total energy at point X also must be 40 J.

For P.E to be maximum K.E. must be zero.

Hence P.E.=56.25J

We can come to the conclusion that potential energy will have the maximum value at maximum height.