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Nutka1998 [239]

2 years ago

7

A stereo speaker produces a pure \"E\" tone, with a frequency of 329.6 Hz. What is the period of the sound wave produced by the

speaker? What is the wavelength of this sound wave as it travels through air with a speed of about 341 m/s? What is the wavelength of the same sound wave as it enters some water, where it has a speed of about 1480 m/s?

1 answer:

olya-2409 [2.1K]2 years ago

8 0

Answer:

0.003034 s

1.035 m

4.5 m

Explanation:

$f$ = frequency of the tone = 329.6 Hz

$T$ = Time period of the sound wave

we know that, Time period and frequency are related as

$T =\frac{1}{f}\\T =\frac{1}{329.6}\\T = 0.003034 s$

$v$ = speed of the sound in the air = 341 ms⁻¹

wavelength of the sound is given as

$\lambda =\frac{v}{f} \\\lambda =\frac{341}{329.6}\\\lambda = 1.035 m$

$v$ = speed of the sound in the water = 1480 ms⁻¹

wavelength of the sound in water is given as

$\lambda =\frac{v}{f} \\\lambda =\frac{1480}{329.6}\\\lambda = 4.5 m$

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The car A has a mass of 1200 kg.

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The momentum before collision is-

$p_{i} =m_{1} v_{1} +m_{2} v_{2}$

[Here p stand for momentum.]

We are asked to calculate the final momentum of the system after collision.

The answer of the question is based law of conservation of linear momentum.

As per law of conservation of linear momentum the sum total linear momentum for an isolated system is always constant.Hence irrespective of the type of collision[elastic and inelastic],the momentum of the system is always constant which is a universal truth.

Let after the collision the velocity of A and B are $v'_{1} \ and\ v'_{2}$

Hence the final momentum of the system is-

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For example, when a solid melts then it means heat is absorbed by it due to which its molecules have gained energy. As a result, they collide with each other and hence, entropy will increase.

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In separation molecules are separated from each other leading to a decrease in energy. Hence, entropy will also decrease.

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3 years ago

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The question provided very little information about this motion. Therefore, replace these quantities with letters. These unknown quantities should not appear in the conclusion if this question is actually solvable.

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This answer will approach this question in two steps:

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<h3>Centripetal Force when the car is about to skid</h3>

The question gave no information about the distance that the car has travelled before it skidded. However, information about the angular displacement is indeed available: the car travelled (without skidding) one-quarter of a circle, which corresponds to $90^\circ$ or $\displaystyle \frac{\pi}{2}$ radians.

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