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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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ApprovedApproved Tutor Answer0 Years ago

To solve the problem of the balloon and the mass being released, we need to analyze the forces acting on both the balloon and the mass. Let's break it down step by step.

Understanding the Forces at Play

When the balloon is descending with a constant acceleration \( a \), it is important to recognize that this means the net force acting on the balloon is directed downwards. The forces involved include the gravitational force acting on the balloon and the buoyant force acting upwards. The equation for the net force can be expressed as:

Net Force on Balloon:

F_net = M \cdot g - F_b = M \cdot a

Where:

  • \( M \) is the mass of the balloon.
  • \( g \) is the acceleration due to gravity.
  • \( F_b \) is the buoyant force.
  • \( a \) is the downward acceleration of the balloon.

Analyzing the Released Mass

When the mass \( m \) is released from the balloon, it begins to rise with the same acceleration \( a \). For the mass to rise, the net force acting on it must also be directed upwards. The forces acting on the mass \( m \) include its weight and the buoyant force. The equation for the net force on the mass can be written as:

Net Force on Mass:

F_net = F_b - m \cdot g = m \cdot a

Setting Up the Equations

Now, we have two equations to work with. The first equation for the balloon gives us:

M \cdot g - F_b = M \cdot a

And for the mass \( m \):

F_b - m \cdot g = m \cdot a

Relating the Two Equations

From the first equation, we can express the buoyant force \( F_b \) as:

F_b = M \cdot g - M \cdot a

Now, substituting this expression for \( F_b \) into the second equation gives us:

(M \cdot g - M \cdot a) - m \cdot g = m \cdot a

Solving for Mass \( m \)

Rearranging the equation leads to:

M \cdot g - M \cdot a - m \cdot g = m \cdot a

M \cdot g - M \cdot a = m \cdot g + m \cdot a

M \cdot g - M \cdot a = m \cdot (g + a)

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

m = \frac{M \cdot (g - a)}{g + a}

Final Thoughts

This equation gives us the mass \( m \) that, when released from the balloon, will rise with the same acceleration \( a \) as the balloon is descending. It’s a neat interplay of forces that illustrates the principles of buoyancy and acceleration in a gravitational field. If you have any further questions or need clarification on any part of this explanation, feel free to ask!