Concept explainers
(a)
The show that the reflected wave has frequency of
(a)
Answer to Problem 18P
The reflected wave has frequency of
Explanation of Solution
Write the expression for the frequency as seen by the car.
Here,
Write the expression for the frequency of the reflected wave.
Here,
Conclusion:
Use
Therefore, the reflected wave has frequency of
(b)
The show that the beat frequency can be written as
(b)
Answer to Problem 18P
The beat frequency can be written as
Explanation of Solution
Use the expression for the frequency obtained in (a) and simplify.
The expression for the beat frequency is,
Use
Conclusion:
Therefore, the beat frequency can be written as
(c)
The beat frequency measured for a car speed of 30.0 m/s if the microwaves have frequency 10.0 GHz.
(c)
Answer to Problem 18P
The beat frequency measured for a car speed of 30.0 m/s if the microwaves have frequency 10.0 GHz is
Explanation of Solution
Rewrite the expression for beat frequency
Use
Conclusion:
Substitute
Therefore, the beat frequency measured for a car speed of 30.0 m/s if the microwaves have frequency 10.0 GHz is
(d)
If the beat frequency measured is accurate to
(d)
Answer to Problem 18P
The velocity measured is accurate to
Explanation of Solution
The expression for change beat frequency is,
Rearrange in terms of v.
Conclusion:
Substitute
Therefore, the velocity measured is accurate to
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Chapter 1 Solutions
Modern Physics
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