Concept explainers
(a)
The initial upward acceleration of the balloon when it is released from sea level.
(a)
Answer to Problem 52P
Explanation of Solution
Given:
Radius of the balloon
Total mass (mass of the balloon + mass of the helium + mass of the equipment)
Formula used:
FIGURE: 1
In the figure 1,
Let us apply the Newton’s second law, that is
Using Archimedes principle, buoyant force
Applying
Since balloon is in spherical shape, volume of the balloon is,
And hence, buoyant force,
Where,
Substituting for buoyant force in equation
Calculation:
Substituting the numerical values in equation
Conclusion:
The initial upward acceleration of the balloon when it is released from sea level is
(b)
The terminal velocity of the ascending balloon.
(b)
Answer to Problem 52P
Explanation of Solution
Given:
Radius of the balloon
Total mass (mass of the balloon + mass of the helium + mass of the equipment)
Drag force of the balloon is
Where,
Formula used:
Let
Let us apply the Newton’s second law, which is
Substituting for
Calculation:
Substituting the numerical values in equation
Conclusion:
The terminal velocity of the ascending balloon is
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Chapter 13 Solutions
Physics for Scientists and Engineers
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