A ball is rising through a liquid with constant speed. The ratio of density of liquid to that of material of ball is 3 : 1. The ratio of viscous force to the weight of the ball is:

Options

A. `1:3`
B. `2:1`
C. `1:4`
D. `4:1`

Answer

B

Explanation

Here `6pietarv+4/3pir^(3)pg`
`=4/3pir^(3)3.p.g`
or `6pietarv=4/3pir^(3)g(3p-p)`
`F=6pietarv`
`=4/3pir^(3)xx2p.g=8/3pir^(3)pg`
Ratio `F/W=(8/3pir^(3)pg)/(4/3pir^(3)pg)=2/1`
`therefore` Correct choice is (b).