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a balloon is descending at a consatnt acceleration a. the mass of balloon is M.whwn a mass m is released from the balloon,its starts rising with the same acceleration a.what is the value of m..??

Profile image of Vandana Kumari
11 Years agoGrade Select Grade
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Profile image of Askiitians Tutor Team
ApprovedApproved Tutor Answer1 Year ago

To tackle this problem, we need to analyze the forces acting on both the balloon and the mass that is released. The scenario involves a balloon descending with a constant acceleration and a mass that, once released, begins to rise with the same acceleration. Let's break this down step by step.

Understanding the Forces at Play

First, let's consider the forces acting on the balloon. The balloon has a mass \( M \) and is descending with an acceleration \( a \). According to Newton's second law, the net force acting on the balloon can be expressed as:

  • Weight of the balloon: \( W_b = Mg \)
  • Net force: \( F_{net} = Ma \)

Since the balloon is descending, the net force acting on it is the difference between the buoyant force (upward) and the weight (downward). Therefore, we can write:

Buoyant force - Weight = Net force

Let’s denote the buoyant force as \( F_b \). Thus, we have:

F_b - Mg = -Ma

Analyzing the Released Mass

Now, when the mass \( m \) is released from the balloon, it starts to rise with the same acceleration \( a \). For the mass \( m \), the forces acting on it are:

  • Weight of the mass: \( W_m = mg \)
  • Net force on the mass: \( F_{net} = ma \)

Since the mass is rising, the net force acting on it can be expressed as:

Buoyant force - Weight = Net force

In this case, the buoyant force acting on the mass \( m \) must overcome its weight for it to rise. Therefore, we can write:

F_b - mg = ma

Setting Up the Equations

Now we have two equations:

  • For the balloon: \( F_b = Mg - Ma \)
  • For the mass: \( F_b = mg + ma \)

Since both expressions equal the buoyant force \( F_b \), we can set them equal to each other:

Mg - Ma = mg + ma

Solving for the Mass \( m \)

Now, let’s rearrange this equation to isolate \( m \):

Mg - Ma - ma = mg

Factor out \( m \) from the right side:

Mg - Ma = m(g + a)

Now, we can solve for \( m \):

m = (Mg - Ma) / (g + a)

Final Thoughts

This equation gives us the mass \( m \) that, when released from the balloon, will rise with the same acceleration \( a \). It’s important to note that the relationship between the forces and the resulting motion is a direct application of Newton's laws, illustrating how forces interact in a dynamic system.

In summary, the value of the mass \( m \) can be calculated using the derived formula, which takes into account the mass of the balloon, the gravitational force, and the acceleration. This problem beautifully demonstrates the principles of dynamics and the interplay of forces in a real-world scenario.