Two spherical raindrops of equal are falling vertically through air with a terminal velocity of `1ms^(-1)`. What would be the terminal speed if the two drops were to coalesce to form a large spherical drop.

Explanation

`v alpha r^(2) therefore v_(2)/v_(1=((r_(2))/(r_(1))^(2), r_(2)=(3sqrtn)r_(1) therefore v_2/v_(1)=(3sqrtn)^(2)=(2)^(2/3)`
`therefore v_(2)=(2^(2/3)) v_(1)=1.587(1)=1.587ms^(-1)`