# The masses of two planets are in the ratio 1 : 2. Their radii are in the ratio 1 : 2. The acceleration due to gravity on the planets are in the ratio. Option 1) 1 : 2 Option 2) 2 : 1 Option 3) 3 : 5 Option 4) 5 : 3

As we learnt in

Acceleration due to gravity (g) -

Force extended by earth on a body is gravity.

Formula:    $g=\frac{GM}{R^{2}},$

$g=\frac{4}{3}\pi \rho \, GR$

$g\rightarrow$ gravity

$\rho \rightarrow$ density of earth

$R \rightarrow$ Radius of earth

- wherein

It's average value is $9.8\: m/s^{2}\; \; or \; \; 981cm/sec^{2}\; or\; 32feet/s^{2}$ on the surface of earth

$\frac{g_{1}}{g_{2}}=\sqrt{\frac{M_{1}}{M_{2}}.\frac{R_{2}^{2}}{R_{1}^{2}}}$  $=\sqrt{\frac{1}{2}.4}= \sqrt{2}$

Option 1)

1 : 2

This is correct option

Option 2)

2 : 1

This is incorrect option

Option 3)

3 : 5

This is incorrect option

Option 4)

5 : 3

This is incorrect option

### Preparation Products

##### Knockout BITSAT 2021

It is an exhaustive preparation module made exclusively for cracking BITSAT..

₹ 4999/- ₹ 2999/-