 
       
      
    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.
1 : 2
2 : 1
3 : 5
5 : 3
 
                
                  As we learnt in
Acceleration due to gravity (g) -
Force extended by earth on a body is gravity.
Formula:    
 gravity
 density of earth
 Radius of earth
- wherein
It's average value is  on the surface of earth

   
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
