COMEDK · Physics · 5. Laws of Motion
A balloon with mass \(m\) is descending down with an acceleration \(a\) (where, \(a < g\) ). How much mass should be removed from it so that it starts moving up with an acceleration \(a\) ?
- A \(\frac{2 m a}{g+a}\)
- B \(\frac{2 m a}{g-a}\)
- C \(\frac{m a}{g+a}\)
- D \(\frac{m a}{g-a}\)
Answer & Solution
Correct Answer
(A) \(\frac{2 m a}{g+a}\)
Step-by-step Solution
Detailed explanation
When the balloon is descending down with an acceleration \(a\), where, \(B=\) buoyant force. Here, we should assume that while removing some mass the volume of balloon and hence buoyant force will not change. Let the new mass of the balloon is \(m^{\prime}\), so On solving Eqs.…
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