$A$ black hole is a:

Two point masses $A$ and $B$ having masses in the ratio $4 : 3$ are separated by a distance of $1\, m$. When another point mass $C$ of mass $M$ is placed in between $A$ and $B$,the gravitational force between $A$ and $C$ is $\frac{1}{3}$ of the gravitational force between $B$ and $C$. Then the distance of $C$ from $A$ is:

Find the acceleration of our galaxy due to the nearest comparably sized galaxy. The approximate mass of each galaxy is $8 \times 10^{11}$ solar masses,and they are separated by $2 \times 10^6$ light-years. Each galaxy has a diameter of $10^5$ light-years. (Assume $1 \text{ light-year} \approx 10^{16} \text{ m}$,gravitational constant $G \approx 10^{-10} \text{ Nm}^2/\text{kg}^2$,and mass of the Sun $= 2.0 \times 10^{30} \text{ kg}$)

The gravitational force between two point masses $m_1$ and $m_2$ at a separation $r$ is given by $F = k \frac{m_1 m_2}{r^2}$. The constant $k$:

Explain the principle of superposition for gravitational force.

The value of $G$ on Earth is $6.67 \times 10^{-11} \ Nm^2/kg^2$. What is the value of $G$ on the Moon?