8. Centripetal Forces & Gravitation

Two small aluminum spheres, each of mass $0.0250\mathrm{kg}$, are separated by a distance of $80.0\mathrm{cm}$. What is the magnitude of the gravitational force between them? (Use $G=6.67\times {10}^{-11}$ $N{m}^2/{\mathrm{kg}}^2$)

Which of the following does not cause gaps in planetary rings?

What is the primary reason the Moon always keeps the same face toward the Earth?

In the context of gravitational forces in two dimensions, where is Earth's gravitational force always directed at the surface?

Which of the following is a general characteristic of the four Jovian planets in our solar system?

Which pair of forces are balanced in a state of gravitational equilibrium?

If a ball is thrown vertically upward with the same initial speed on both the Earth and the Moon, how much longer will the total time of flight (up and down) be on the Moon compared to the Earth?

When an object is in free fall near Earth's surface and air resistance is neglected, what is the only force acting on it?

The phases of the $\mathrm{Moon}$ are a result of which of the following?

Which of the following best describes the relationship between gravitational force and mass according to Newton's law of universal gravitation in two dimensions?

Which of the following best describes spring tides in the context of gravitational forces in $2D$?

If a ball is moved from the surface of $Earth$ to the surface of $Moon$, what happens to its $mass$?

In the context of gravitational forces in two dimensions, which of the following best describes the origin of the energy released during an earthquake?

Which of the following events is primarily responsible for causing tides on $\mathrm{Earth}$?

Which of the following factors affect the magnitude of the gravitational force between two point masses in two dimensions? $F=\frac{\mathrm{G\; m\_1\; m\_2}}{r^2}$