Concept explainers
(a)
The quantity of energy the burner must transfer to the air in the balloon.
(a)
Answer to Problem 21P
The quantity of energy the burner must transfer to the air in the balloon is
Explanation of Solution
Write the expression from
Here,
Write the expression for number of moles.
Here,
Write the expression for density.
Here,
Write the expression for total force exerts on the balloon under equilibrium condition.
Here,
Write the expression for quantity of energy transfer to the air contains diatomic gas.
Here,
Conclusion:
Substitute equation (II) and (III) in equation (I) and rearrange it.
Rewrite the above equation for hot temperature.
Here,
Rewrite the equation for outside cargo air temperature.
Here,
Compare the equation (VI) and (VII) to solve for
Replace
Substitute equation (VIII) in the above equation.
Substitute
Rewrite the expression (I) for warmed temperature.
Substitute above equation in the equation (V).
Substitute
Therefore, the quantity of energy transfer to the air in the balloon is
(b)
The mass of the propane.
(b)
Answer to Problem 21P
The mass of the propane is
Explanation of Solution
Write the expression from the relation between heat energy and the quantity of heat released from the propane burned.
Here,
Rearrange the above equation for mass.
Conclusion:
Substitute
Therefore, the mass of the propane is
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Chapter 21 Solutions
Physics for Scientists and Engineers with Modern Physics Technology Update
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