JEE Mains · Physics · STD 11 - 4.1 newtons laws of motion
A balloon has mass of \(10\,g\) in air. The air escapes from the balloon at a uniform rate with velocity \(4.5\,cm / s\). If the balloon shrinks in \(5\,s\) completely. Then, the average force acting on that balloon will be (in dyne).
- A \(3\)
- B \(9\)
- C \(12\)
- D \(18\)
Answer & Solution
Correct Answer
(B) \(9\)
Step-by-step Solution
Detailed explanation
\(F =\frac{ dm }{ dt } v\) \(=\frac{10 g }{5 s }\left(4.5 \frac{ cm }{ s }\right)=9 \frac{ gcm }{ s ^{2}}=9\,dyne\)
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