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3 years ago

5

Which of the following would not increase the velocity of a sound wave in air? A. lowering the humidity of the air. B. increasin

g the temperature of the air. C. increasing the wind speed in the direction the wave is traveling. D. lowering the density of the air

2 answers:

expeople1 [14]3 years ago

8 0

Answer:

Lowering the humidity of the air.

Explanation:

The mathematical formula for the speed of sound wave is given by :

$v=\sqrt{\dfrac{\gamma RT}{M}}$

Where

$\gamma$ is the adiabatic constant

T is the temperature of air

M is the molecular mass of the gas

or

$v=\sqrt{\dfrac{B}{\rho}}$

B is the bulk modulus

$\rho$ is the density of the air

As the humidity of the air increases, then the number of water molecules increase. As a result, molar mass decreases and ultimately the speed of sound increases and vice versa.

So, the correct option is (A) " lowering the humidity of the air ". Hence, this is the required solution.

Rashid [163]3 years ago

6 0

A. Lowering the humidity of the air.

Hope this helps!

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Answer:

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a = acceleration

t = time

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Why is it impossible to create a perpetual motion machine?

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Answer:

It is impossible to create a perpetual motion machine because some of the energy will always be lost in the conversion and therefore it will eventually stop.

Correct Answer : Option B

Explanation:

The perpetual motion machine is impossible machine as it is hypothetical working machine which would be in motion for an indefinite time in continuity of the motion. The continuity of motion for an indefinite time would mean that the working principle of the machine would never allow the dissipation of energy from the machine and all the machine would ultimately reserve all the energy and be converting it into forms without any loss.

This working principle is violation of first and second laws of thermodynamics and hence a machine will eventually lose some of its energy in every conversion of the working cycle and hence there will be a time where the machine would be stopped, and hence a perpetual motion machine cannot be made.

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3 years ago

Calculate the separation between the two lowest levels for an O2 molecule in a one-dimensional container of length 5.0 cm. At wh

MariettaO [177]

Answer:

The separation between the two lowest levels = $1.24 * 10^{-39}J$

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Explanation:

Knowing the formula

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Answer:

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Put the value into the formula

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Using formula of frictional force

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