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Gnoma [55]
2 years ago
10

A train is traveling west at a velocity of 25 m/s. Another train is traveling east directly toward the west-bound train at a vel

ocity of 15 m/s. The west-bound train blows its whistle with a frequency of 600 Hz when the two trains are 1000 m apart and then blows its whistle again 10 seconds later. For passengers on the east-bound train, how will the perceived frequency of the first whistle compare with the perceived frequency of the second whistle
Physics
1 answer:
dusya [7]2 years ago
4 0

(a) The frequency observed by the passenger on the east-bound train when they are 1000 m apart is 675.5 Hz.

(b) After 10 seconds, the frequency observed by the passenger on the east-bound train will be greater than the frequency observed when they are 1000 m apart.

<h3>Observed frequency</h3>

The frequency observed by the passenger on east-bound train is calculated by applying Doppler shift formula.

f = f_0(\frac{v \pm v_0}{v\pm v_s} )

where;

  • f is observed frequency
  • f₀ is original frequency or source frequency
  • v is speed of sound
  • v₀ is speed of observer (positive when moving towards source)
  • vs is source frequency (negative when moving towards observer)

<h3>when the two trains are 1000 m apart</h3>

f = 600(\frac{343 +15}{343-25} )\\\\f = 675.5 \ Hz

The frequency observed by the passenger increases with decrease in distance between the two trains.

Thus, after 10 seconds, the frequency observed by the passenger on the east-bound train will be greater than the frequency observed when they are 1000 m apart.

Learn more about Doppler shift here: brainly.com/question/23841569

#SPJ1

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Explanation:

Here is the complete question

A ball is thrown straight up from the ground with speed v₀ . At the same instant, a second ball is dropped from rest from a height D , directly above the point where the first ball was thrown upward. There is no air resistance

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Express your answer in terms of the variables D ,v₀ , and appropriate constants..

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0 = v₀² - 2gs

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