Concept explainers
(a)
The frequency heard by passenger in the car.
(a)
Answer to Problem 71CP
The frequency heard by passenger in the car is
Explanation of Solution
Write the expression for the frequency of sound heard by the passengers in the car.
Here,
The car stopped and not moving hence the speed of the observer will be zero.
Rewrite equation (I) by substituting
The train is
Hence using hypotenuse theorem the distance between train and the car is.
Here,
Write the expression for
Conclusion:
Substitute,
Substitute,
Substitute,
Therefore, the frequency heard by passenger in the car is
(b)
The range of frequencies heard by the passengers in the car.
(b)
Answer to Problem 71CP
The range of frequencies heard by the passengers in the car is in between
Explanation of Solution
As train approaches and departs, the angle
Write the expression for maximum frequency.
Write the expression for maximum frequency.
Conclusion:
Substitute,
Substitute,
Therefore, the range of frequencies heard by the passengers in the car is in between
(b)
The frequency heard by the passengers in car when car is trying to beat the train.
(b)
Answer to Problem 71CP
The frequency heard by the passengers in car when car is trying to beat the train is
Explanation of Solution
Write the Doppler equation.
Let
Write the expression for
Conclusion:
Substitute,
Substitute,
Therefore, the frequency heard by the passengers in car when car is trying to beat the train is
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Chapter 17 Solutions
Physics for Scientists and Engineers with Modern Physics Technology Update
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