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A spherical liquid drop of radius R acquires the terminal velocity v1 when falls through a gas of viscosity . Now the drop is broken into 64 identical droplets and each droplet acquires terminal velocity v2 falling through the same gas. The ratio of terminal velocities v1/v2 is .
(4) 16
Volume is conserved: 43 R3=64 43 r3 r= R4
Terminal velocity v= 2r2( - )g9 v r2
v1v2= ( Rr )2=42=16
Answer: (4)
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