A small spherical ball of radius r, falling through a viscous medium of negligible density has terminal velocity 'v'. Another ball of the same mass but of radius 2r, falling through the same viscous medium will have terminal velocity:
- 4v
- 2v
- v4
- v2
Answer
(4) v2
Solution
Negligible density of medium no buoyancy
At terminal velocity: mg=6 rv (Stokes' law)
m is the same v 1r
v'=v r2r= v2
Answer: (4)