JEE Mains · Physics · STD 11 - 9.1 fluid mechanics
The terminal velocity of a metallic ball of radius 6 mm in a viscous fluid is \(20 cm / s\). The terminal velocity of another ball of same material and having radius 3 mm in the same fluid will be _________ \(cm / s\).
- A 10
- B 5
- C 2.5
- D 15
Answer & Solution
Correct Answer
(B) 5
Step-by-step Solution
Detailed explanation
We know: Terminal velocity \(\propto(\text { radius })^2\) \(\frac{\left( v _{ T }\right)_1}{\left( v _{ T }\right)_2}=\left(\frac{6}{3}\right)^2\) \(\left( v _{ T }\right)_2=\frac{\left( v _{ T }\right)_1}{4}=5 cm / sec\)
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