The mass of the planet Gallifrey is 8 times the mass of the Earth.
- let the gravitational field of Earth = g
- let the radius of the Earth = R
- gravitational field of Gallifrey = 2g
- radius of Gallifrey = 2R
<h3>What is gravitational potential energy?</h3>
- This is the work done in moving an object to a certain distance against gravitational field.
The gravitational field strength of the Earth is given as follows;

The gravitational field strength of the Planet Gallifrey is calculated as follows;


Thus, the mass of the planet Gallifrey is 8 times the mass of the Earth.
Learn more about gravitational field strength here: brainly.com/question/14080810
Ans: D
In a projectile motion, horizontal velocity is constant, while the ball is travelling at a constant vertical acceleration due to the gravity (9.81 ms-2 on Earth).
A. Because they reflect their color and absorb all the others
Answer:
480J
Explanation:
Using the formula:
Delta U = Q - W
Q:Heat (J)
Delta U: Changes in internal Energy (J)
W:Work (J)
We can plug in the give numbers, Q and W.
Delta U = 658J - 178J = 480J