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2 years ago

The speed of sound in air is 331 m/s. what is the plane's speed in terms of the speed of sound?

1 answer:

5 0

<span>The initial speed, u of plane in terms of velocity of sound which may be taken as U
u=142/331=0.429*U
It crosses the sound barrier after says t seconds then we have 331-142=23.1*t or t is given 8.18 s exactly t=9/11s.
After 18 seconds the plane will traveling with velocity V
V=142+18*23.1=557.8 m/s==1.685*U</span>

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3 years ago

Sound wave A delivers 2 J of energy in 2 s. Sound wave B delivers 10 J of energy in 5 s. Sound wave C delivers 2 mJ of energy in

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2 years ago

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Answer:

(a): emf = $\rm 2\pi f NBA\sin(2\pi ft).$

(b): Amplitude of alternating voltage = 20.942 Volts.

Explanation:

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Area of the coil = A.
Number of turns of coil = N.
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(a):

The magnetic flux through the coil is given by

$\phi = \vec B \cdot \vec A=BA\cos\theta$

where,

$\vec A$ = area vector of the coil directed along the normal to the plane of the coil.

$\theta$ = angle between $\vec B$ and $\vec A$ .

Assuming, the direction of magnetic field is along the normal to the plane of the coil initially.

At any time t, the angle which magnetic field makes with the normal to the plane of the coil is $2\pi ft$

Therefore, the magnetic flux linked with the coil at any time t is given by

$\phi(t) = NBA\cos(2\pi ft)$

According to Faraday's law of electromagnetic induction, the emf induced in the coil is given by

$e=-\dfrac{d\phi}{dt}\\=-\dfrac{d(NBA\cos(2\pi ft))}{dt}\\=-NBA(-2\pi f\sin(2\pi ft))\\=2\pi f NBA\sin(2\pi ft).$

(b):

The amplitude of the alternating voltage is the maximum value of the emf and emf is maximum when $\sin(2\pi ft)=1.$

Therefore, the amplitude of the alternating voltage is given by

$e_o = 2\pi ft NBA.$

We have,

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$e_o = 2\pi \times 33.33\times 100\times 0.1\times 10^{-2}=20.942\ Volts.$

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3 years ago

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Convection currents are driven by the buoyancy
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Learn more about potential energy:

brainly.com/question/1198647

brainly.com/question/10770261

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2 years ago

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