JEE Main 2024 Physics question
Small water droplets of radius 0.01 mm are formed in the upper atmosphere and falling with a terminal velocity of 10 cm/s. Due to condensation, if 8 such droplets are coalesced and formed a larger drop, the new terminal velocity will be ………..cm/s.
Answer: 40
Solution
8 droplets make a drop of radius 2r; ∝ r², so v = 4 × 10 = 40 cm/s.