JEE Mains · Physics · STD 11 - 9.1 fluid mechanics
The velocity of a small ball of mass ' \(m\) ' and density \(d _{1}\), when dropped in a container filled with glycerine, becomes constant after some time. If the density of glycerine is \(d _{2}\), then the viscous force acting on the ball, will be
- A \(m g\left(1-\frac{d_{1}}{d_{2}}\right)\)
- B \(m g\left(1-\frac{d_{2}}{d_{1}}\right)\)
- C \(m g\left(\frac{d_{1}}{d_{2}}-1\right)\)
- D \(m g\left(\frac{d_{2}}{d_{1}}-1\right)\)
Answer & Solution
Correct Answer
(B) \(m g\left(1-\frac{d_{2}}{d_{1}}\right)\)
Step-by-step Solution
Detailed explanation
\(F_{V}=m g-F_{B}\) \(=m g-\left(\frac{m}{d_{1}} \times d_{2}\right) g\) \(=m g\left(1-\frac{d_{2}}{d_{1}}\right)\)
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