The nucleus of an atom is about 10-15 m in size; this means it is about 10-5 (or 1/100,000) of the size of the whole atom. A good comparison of the nucleus to the atom is like a pea in the middle of a racetrack. (10-15 m is typical for the smaller nuclei; larger ones go up to about 10 times that.)
Some thing that is done physically like with a persons hands and such
Velocity is computed using the formula:

Where:
V = speed
d = distance traveled
t = time/period
First you need to consider that the orbit is circular. To get the measurement or the distance going around Earth, you will need to get the circumference of the path.

Where:
C = circumference
π = 3.14
r = radius
The Earth has a radius of 6,400km, but you also need to consider that the satellite is orbiting above the surface of the Earth, so you add in the 2,000km to that radius.
r = 6,400Km + 2,000Km =
8,400Km
Next step is to insert that into our circumference formula:



The distance traveled would then be
52,778.76KmNow that we have the distance, we can then get the velocity:



The speed of the satellite is
4,398.23km/hr.
A single reflection, like shouting at the side of a mountain and hearing
your voice come back to you, is an 'echo'.
Multiple reflection, like clapping your hands once inside a large room,
is 'reverberation'.