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Two trains A and B are approaching a pla...

Two trains A and B are approaching a platform from opposite directions. The siren in the station is making a sound at a frequency 4 kHz. The passengers in trains A and B hear siren at frequencies 4.5 and 5 kHz respectively. Then the velocities of the trains A and B are (velocity of sound in air = `340 m//s)`

A

`42.5 m//s , 85 m//s`

B

`75 m//s,55 m//s`

C

`85 m//s, 8.5 m//s`

D

`42.5 m//s, 6.25 m//s`

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TARGET PUBLICATION-Sound-Exercise
  1. A drone fitted with siren in flying directly away from the drone opera...

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  2. A siren placed at a railway platform is emitting a sound of frequency ...

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  3. Two trains A and B are approaching a platform from opposite direction...

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  4. A train has just completed a U-curve in a track which is a semicircle....

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  5. A car is moving with a speed of 72 km-hour^(-1) towards a roadside sou...

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  6. The velocity of sound is greatest in

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  7. A heavy ball of mass M is suspended from the ceiling of a car by a lig...

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  8. The transverse displacement of a string clamped at both ends is by y (...

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  9. Two boys stand close to a long straight metal pipe, at some distance f...

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  10. A uniform rope of length L and mass m1 hangs vertically from a rigid s...

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  11. A granite rod of 60 cm length is clamped at its middle point and is se...

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  12. At a temperature of 314 K and a pressure of 100 kPa, the speed of soun...

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  13. The extension in a string, obeying Hooke’s law, is x. The speed of the...

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  14. When sound is produced in an aeroplane moving with a velocity of 250 m...

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  15. Neon is 20 times heavier than hydrogen. The equal volumes of hydrogen ...

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  16. Sound waves in air are always longitudinal, because

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  17. Which of the following doesn’t produce a sound wave?

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  18. The ratio of velocity of sound in hydrogen and chlorine at STP is

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  19. Assertion: For sound waves, air is rarer medium than water. Reason: ...

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  20. Which of the following statements is true for wave motion ?

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