AP EAMCET2013PhysicsMechanical Properties of Fluids
The terminal velocity of a liquid drop of radius ' r ' falling through air is v . If two such drops are combined to form a bigger drop, the terminal velocity with which the bigger drop falls through air is (ignore any buoyant force due to air)
Options
- A2 v
- B2 v
- C[3] 4 v
- D[3] 2 v
Correct answer
C. [3] 4 v
Step-by-step solution
Terminal velocity v= 2 9 r^2( - ) g When, the two drops of same radius r coalesce then radius of new drop is R . array llrl & & 4 3 R^3 & = 4 3 r^3+ 4 3 r^3 & & R & =2^ 1 / 3 r Critical velocity & r^2 & & v v₁ & = r^2 2^ 2 / 3 r^2 & & V₁ & = [3] 4 v array