Name: Tides Explained With Simulations
Uploaded: 2019-07-19
Duration: 3 min 33 s
Description: The regular rise and fall of the ocean waters are known as tides. In this video, we will learn it in the simplest way and the reason behind it.

Question

What are the units of gravitational constant

(G)

?

Accepted Answer

The gravitational constant is defined as the force of attraction between two bodies of unit mass separated by a unit distance.

According to Newton's law of gravitation,

$F = G \frac{m_{1} m_{2}}{R^{2}}$

From this equation, one can write,

$G = \frac{F \times R^{2}}{m_{1} \times m_{2}}$
Thus, the unit of $G$ would depend upon the units of force $(F)$ , distance $(R)$ and mass $(m_{1} & m_{2})$ .

In the SI system, the unit of force $(F)$ is newton $(N)$ , that of distance $(R)$ is metre $(m)$ , and the unit of mass $(m_{1} & m_{2})$ is kilogram $(kg)$ . So, the SI unit of the gravitational constant $(G)$ is given by

$\frac{newton \times {(metre)}^{2}}{kilogram \times kilogram} = \frac{N \times m^{2}}{{kg}^{2}} = N \times m^{2} \times {kg}^{- 2}$

A newton $(N)$ is defined as $1 \frac{kg \times m}{s^{2}} = kg \times m \times s^{- 2}$

$∴ N \times m^{2} \times {kg}^{- 2} = kg \times m \times s^{- 2} \times m^{2} \times {kg}^{- 2} = {kg}^{(1 + (- 2))} \times m^{(1 + 2)} \times s^{- 2} = {kg}^{- 1} \times m^{3} \times s^{- 2} = m^{3} {kg}^{- 1} s^{- 2}$

Thus, the SI unit of the gravitational constant $(G)$ is $N m^{2} {kg}^{- 2}$ or $m^{3} {kg}^{- 1} s^{- 2}$ .

What are the units of gravitational constant $(G)$ ?

Important Questions on Gravitation

Learn and Prepare for any exam you want !

What are the units of gravitational constant (G)?

Important Questions on Gravitation

Learn and Prepare for any exam you want !

What are the units of gravitational constant $(G)$ ?