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A toy-car, blowing its horn, is moving w...

A toy-car, blowing its horn, is moving with a steady speed of 5 m//s, away from a wall. An observer, towards whom the toy car is moving, is able to heat 5 beats per second. If the velocity of sound in air is 340 m/s, the frequency of the horn of the toy car is close to :

A

340 Hz

B

510 Hz

C

170 Hz

D

680 Hz

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The correct Answer is:
C
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ALLEN -WAVES AND OSCILLATIONS-Part-1(Exercise-05)[A]
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  2. A sound absorber attenuates the sound level by 20 dB. The intensity de...

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  3. While measuring the speed of sound by performing a resonance column ex...

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  4. A wave travelling along the x-axis is described by the equation v(x, t...

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  5. Three sound waves of equal amplitude have frequencies (n-1), n, (n + 1...

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  6. A motor cycle starts from rest and accelerates along a straight path a...

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  7. The equation of a wave on a string of linear mass density 0.04 kgm^(-1...

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  8. The transverse displacement y(x, t) of a wave on a string is given by ...

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  9. Statement-1: Two longitudinal waves given by equation y(1)(x,t)=2asin(...

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  10. A transverse wave travelling along the positive x-axis, given by y=A s...

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  11. A cylindrical tube, open at both ends, has a fundamental frequency f i...

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  12. A sonometer wire of length 1.5m is made of steel. The tension in it pr...

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  13. A pipe of length 85cm is closed from one end. Find the number of possi...

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  14. A train is moving on a straight track with speed 20 ms^(-1). It is blo...

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  15. A bat moving at 10 ms^(-1) towards a wall sends a sound signal of 8000...

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  16. A source of sound emits sound waves at frequency f(0). It is moving to...

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  17. A uniform string of length 20m is suspended from a rigid support. A sh...

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  18. A cylindrical tube, open at both ends, has a fundamental frequency f i...

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  19. Two engines pass each other moving in opposite directions with uniform...

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  20. A toy-car, blowing its horn, is moving with a steady speed of 5 m//s, ...

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