<span>the gravational potential energy of anything on the ground is zero. When calculating potential energy you take height in meters and multiply it by the mass of the object in kilograms and the acceleration of gravity to get a new unit called Joules.
Any object at ground level has a potential energy of zero newtons becuase anything multiplied by zero is zero. An object with mass of 54 kg, 4 meters above the ground has a gravitatinal potential energy of 2116.8 Joules.</span>
I can't make sense of this question. Julie's throwing the ball, so it's leaving her rather than arriving at her ???
First convert 5.5 cm to meters.
(5.5 cm / 1) x (m / 100 cm) = 0.055 m
A typical atom is about 1.0E-10 m in diameter; thus:
0.055 m / 1.0E-10 m = 5.5E8 atoms or 550,000,000 end-to-end atoms in 5.5 cm
Scattering occurs when light changes direction after colliding with particles of matter.