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प्रश्न
Solve the following.
A hot air balloon has a volume of 2800 m3 at 99°C. What is the volume if the air cools to 80°C?

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उत्तर
Given:
V1 = Initial volume = 2800 m3,
T1 = Initial temperature = 99°C = 99 + 273.15 = 372.15 K,
T2 = Final temperature = 80°C = 80 + 273.15 K = 353.15 K
To find: V2 = Final volume
Formula: `"V"_1/"T"_1="V"_2/"T"_2` (at constant n and P)
Calculation:
According to Charles’ law,
`"V"_1/"T"_1="V"_2/"T"_2` (at constant n and P)
∴ V2 = `("V"_1"T"_2)/"T"_1=(2800xx353.15)/372.15` = 2657 m3
The volume of the balloon when the air cools to 80°C is 2657 m3
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