According to the conservation of mechanical energy, the kinetic energy just before the ball strikes the ground is equal to the potential energy just before it fell.
Therefore, we can say KE = PE
We know that PE = m·g·h
Which means KE = m·g·h
We can solve for h:
h = KE / m·g
= 20 / (0.15 · 9.8)
= 13.6m
The correct answer is: the ball has fallen from a height of 13.6m.
35%
5.43/15.6
This is how you calculate the percentage the answer is 35%
The outer surface of the glass expands faster than the inside surface since glass is a fairly good thermal insulator. The outer surface tries to expand without the inner surface doing so at the same time. This is the secret of Pyrex glass. It is more conductive to heat and the inner and outer surface expand (and contract) at the same time.
