If the terminal speed of a sphere of gold (density 19·5 kg/`m^(3)`) is 0.2 m/s in a viscous liquid (density 1.5 kg/`m^(3)`), find the terminal speed of sphere of silver (density `10.5 kg//m^(3)`) of same size in same liquid.

Options

A. 0·2 m/s
B. 0·4 m/s
C. 0.1 m/s
D. 0·3 m/s

Answer

C

Explanation

Terminal velocity v =`(2r2(p-sigma))/(9n)g`
`therefore(v_(2))/(v_(1))=((o_(2)-sigma)/(p_(1)-sigma))` as r and n are same`.
`thereforev_(2)=((10.5-1.5)/(19.5-1.5))xx0.2=0.1ms^(-1)`
Thus correct choice is ©.