This is a good time to review Newton's 3rd law of motion:
"For every action, there is an equal and opposite reaction."
Gravitational force always acts in pairs.
Whatever force the Earth attracts something with,
the thing attracts the Earth with exactly the same force.
If Earth
attracts a person with a gravitational force of <span><span>7.0 × 10² </span>newtons,
the person attracts Earth with a gravitational force of 7.0 × 10² newtons.
Your weight on Earth is the same as the Earth's weight on you !
</span>
Answer: 17.83 AU
Explanation:
According to Kepler’s Third Law of Planetary motion <em>“The square of the orbital period of a planet is proportional to the cube of the semi-major axis (size) of its orbit”. </em>
(1)
Talking in general, this law states a relation between the <u>orbital period</u> 
of a body (moon, planet, satellite, comet) orbiting a greater body in space with the <u>size</u> 
of its orbit.
However, if is measured in <u>years</u>, and is measured in <u>astronomical units</u> (equivalent to the distance between the Sun and the Earth: 
), equation (1) becomes:
(2)
This means that now both sides of the equation are equal.
Knowing 
and isolating from (2):
![a=\sqrt[3]{T^{2}}=T^{2/3}](https://tex.z-dn.net/?f=a%3D%5Csqrt%5B3%5D%7BT%5E%7B2%7D%7D%3DT%5E%7B2%2F3%7D)
(3)
(4)
Finally:
(5)
C. Acceleration is the rate of change of velocity. So at the top of the path, while the velocity is zero, the CONSTANT GRAVITATIONAL ACCELERATION is about 10 m/s^2 (9.8)
Some benefits to solar power:
Isolated power is very abundant on earth.
Is very sustainable (5 billion years of good use)
Eco friendly excluding panel production.
Some disadvantages:
Very expensive to set up
Takes up a lot of space per person
Requires exotic materials to construct
Energy storage is difficult with solar cells compared to fossil fuels.
