Question

Solution

Correct option is

24 cm s–1

Let r be the radius of each small drop. The volume of each drop . Let R be the radius of the big drop formed when 8 small drops coalesce. The volume of the big drop will be 8 times that of the small drop. Hence   i.e., the radius of the big drop is twice the radius of each small drop. Now, if the buoyancy of the drop due to air is neglected, the terminal speed of the small drop is given by The terminal speed of the big drop will be Dividing (i) and (ii), we have  .

SIMILAR QUESTIONS

Q1

A body floats in water with 40% of its volume outside water. When the same body floats in oil, 60% of its volume remains outside oil. The relative density of oil is

Q2

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Q3

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Q4

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Q5

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Q6

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Q7

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Q8

A rain drop of radius r falls in air with a terminal speed vt. What is the terminal speed of a rain drop of radius 2r

Q9

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Q10

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