Concept explainers
(a)
The speed of the car.
Answer to Problem 6TP
The speed of the car is
Explanation of Solution
Given:
The frequency of the car's horn is
Formula used:
The expression for the calculation of the frequency when the source is moving toward the observer is given by
Here,
The expression for the calculation of the frequency when the source is moving away from the observer is given by
Here,
The expression to calculate the mean velocity of the car is given by
Here,
Calculation:
The frequency perceived by the student obtained from the graph when the source is moving towards the observer is
The velocity of the sound in air is
The velocity of the car when the source is moving towards the observer is calculated from the Doppler's effect formula as follows:
The frequency perceived by the student obtained from the graph when the source is moving to away from the observer is
The velocity of the car when the source is moving away from the observer is calculated from the Doppler's effect formula as follows:
The mean velocity of the car is calculated as follows:
Conclusion:
The speed of the car is
(b)
The graph showing the perceived frequency of the car when the car is travelling at twice of speed.
Answer to Problem 6TP
The required graph is plotted.
Explanation of Solution
Given:
The coordinates from the graph when the source is moving towards the observer is
The coordinates from the graph when the source is moving away from the observer is
Calculation:
The graph for the line showing the perceived frequency when the car is travelling at twice speed as follows:
Draw the perpendicular lines at
Figure (1)
Now, draw the line parallel to the
Figure (2)
The graph showing the perceived frequency when the car is travelling at twice of the speed is shown below.
Figure (3)
Conclusion:
Therefore, the required graph is plotted.
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Chapter 17 Solutions
COLLEGE PHYSICS (OER)
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