InterviewSolution
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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
A man is standing beside a railway line listening to the whistle of a passing train. The whistle which has frequency of 1000 Hz suffers an apparent change of 100 Hz. What is the speed of the train ? Velocity of sound `= 333.3 m s^(-1)` |
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Answer» Correct Answer - `16.7 m s^(-1)` |
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| 2. |
A train approaches a stationary observe at a speed of 75 kilometres per hour sounding a whistle of frequency 1000 Hz. What will be the apparent frequency of the whistle to the observes? Velocity of sound `= 332 m s^(-1)` |
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Answer» Correct Answer - `1067 Hz` |
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| 3. |
An observer on a railway station platform observed that as the train passed the station at 96 kmph, the frequency of the whistle appeared to drop by 400 Hz. Find the frequency of the whistle. (Velocity of sound `= 1200 km//h`) |
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Answer» Correct Answer - 2484 Hz |
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| 4. |
A receiver and a source of sonic oscillations of frequency `v_(0) = 2000 Hz` are located along the x-axis. The source swings simple harmonically along the axis with a constant frequency and amplitude `a = 50 cm`. If the frequency band -width registered by the stationary receiver is `Delta v = 200 Hz`, find the value of oscillation frequency of the source. Speed of sound in air `= 340 m s^(-1)` |
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Answer» Correct Answer - 5.4 Hz |
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| 5. |
A source of sound of frequency `1000 H_(Z)` moves unifornly along a straight line with velocity `0.8` times velocity of sound . An observer is located at a distance `l= 250 m` from this line. Find (a) the frequency of the sound at instant when the source is closest to the observer. (b) the distance of the source when he observer no change in the frequency. |
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Answer» Correct Answer - 2777.8 Hz, 320 m |
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| 6. |
A source of sound is moving along a circular orbit of radius `3 meter` with an angular velocity of `10 rad//s`. A sound detector located far away from the source is executing linear simple harmonic motion along the line `BD` with an amplitude `BC = CD = 6 meters`. The frequency of oscillation of the detector is `(5)/(pi)` per second. The source is at the point `A` when the detector is at the point `B`. If the source emits a continuous sound wave of frequency `340 Hz`, Find the maximum and the minimum frequencies recorded by the detector. |
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Answer» Correct Answer - 257.3 Hz, 438.7 Hz |
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| 7. |
Can you go fast enough to have red light appear green ? `lambda ("red") = 6200 Å` and `lambda ("green") = 5400 Å`. |
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Answer» Correct Answer - Speed needed `= 4.4 xx 10^(7) ms` |
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