Two equal drops are falling through air with a steady velocity of 15 cm/s. If the drops coalesce, the new terminal velocity will be
15/(2)cm/s
5×(4)2/3cm/s
15×(4)1/3cm/s
5/(4)2/3cm/s
When the two drops coalesce,r′=(2)1/3r We know that V∝r2 So, terminal velocity =15×21/32 =15×(4)1/3cm/s