Nicholas Copernicus correctly assumed that the planets revolved around the sun but he incorrectly assumed that the planets followed a perfect circle orbit around the sun. It was later on discovered by Johannes Kepler that the planets moved around the sun following an elliptical orbit.
Answer:
The center of mass of the Earth-Moon system is 4.673 kilometers away from center of Earth.
Explanation:
Let suppose that planet and satellite can be treated as particles. The masses of Earth and Moon (
, 
) are 
and 
, respectively. The distance between centers is 384,403 kilometers. The location of the center of mass can be found by using weighted averages:
If 
and 
, then:
The center of mass of the Earth-Moon system is 4.673 kilometers away from center of Earth.
You should put when you will leave, where you will be, and what time you will get back.
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.
When water changes into vapor, it is called evaporation. BONUS: This is formed by the boiling point of water, which is 230°F (Fahrenheit) or 110°C (Celsius).
