Question

The force of attraction between two unit point masses separated by a unit distance is called

• A. gravitational potential
• B. acceleration due to gravity
• C. gravitational field
• D. universal gravitational constant

Answer 1

The correct option is D

universal gravitational constant

The explanation for the correct answer:

Option (D): universal gravitational constant

1. According to Newton's law of gravitation, every particle attracts other particles by a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
2. Numerically it can be represented as: $\mathrm{F}=\mathrm{G}\frac{{\mathrm{m}}_1{\mathrm{m}}_2}{{\mathrm{r}}^2}$; where $\mathrm{G}$ is universal gravitational constant; ${\mathrm{m}}_1\mathrm{and}{\mathrm{m}}_2$ masses of both objects, and $\mathrm{r}$ is the distance between them.
3. If both masses are unit masses then ${\mathrm{m}}_1=1\mathrm{and}{\mathrm{m}}_2=1$ and unit distance means $\mathrm{r}=1$.
4. The formula becomes: $$\begin{gathered} \mathrm{F}=\mathrm{G}\frac{1\times 1}{1} \\ \therefore \mathrm{F}=\mathrm{G} \end{gathered}$$

The explanation for the incorrect answer:

Option (A): gravitational potential

It refers to the work per unit mass needed to move an object to a particular location from a fixed point of reference.

Option (B): acceleration due to gravity

It denoted the net acceleration imparted to an object due to the effect of gravitation.

Option(C): gravitational field

It is a model that is used to explain the effect that a body with a certain mass experiences around itself in space.

Hence, Option(D) is correct.