Two equal drops are falling through air with a steady velocity of 5 cm/sec. If the drops coalesce, the new terminal velocity will be
5x 2cm/sec
5x2 cm/sec
5×(4)1/3cm/sec
5/2cm/sec
vT∝r2. Hence 5∝r2 and v∝R2 or v∝(2)1/3r2∝41/3r2 ∴ v5=(4)1/3 or V=5×(4)1/3cm/sec