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2 years ago

12

Helium (density 0.18 kg/m^3 at 0°C and 1 atm pressure) remains a gas until the extraordinarily low temperature of 4.2 K.What is

the speed of sound in helium at 8 K?

1 answer:

balu736 [363]2 years ago

7 0

Answer:

$166.6396m/sec$

Explanation:

Molar mass of helium = $4\times 10^{-3}kg/mole$

$\gamma$ for helium is 1.67

The velocity of helium in sound at any temperature is given by $v=\sqrt{\frac{\gamma RT}{M}}=\sqrt{\frac{1.67\times 8.314\times 8}{4\times 10^{-3}}}=166.6396m/sec$

R is a constant 8.314 $atm\ mol^{-1}K^{-1}$

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Given

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Answer:

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