A microwave source produces pulses of 20.0-GHz
(a)
The wavelength of the microwave.
Answer to Problem 72P
The wavelength is
Explanation of Solution
Write the expression to calculate the wavelength.
Here,
Conclusion:
Substitute
Thus, the wavelength is
(b)
The total energy of each pulse.
Answer to Problem 72P
The total energy is
Explanation of Solution
Write the expression to calculate the total energy.
Here, U is the total energy, P is the power and t is the time.
Conclusion:
Substitute
Thus, the total energy is
(c)
The average energy density inside the pulse.
Answer to Problem 72P
The average energy density is
Explanation of Solution
Write the expression to calculate the average energy density.
Here, u is the average energy density, r is the radius and l is the length of the pulse.
Write the expression to calculate the length of the pulse.
Use the expression
Conclusion:
Substitute
Thus, the average energy density is
(d)
The amplitude of electric and magnetic field.
Answer to Problem 72P
The amplitude of electric and magnetic field respectively
Explanation of Solution
Write the expression to calculate the magnitude of electric field.
Here,
Write the expression to calculate the magnitude of magnetic field.
Here,
Conclusion:
Substitute
Substitute
Thus, the amplitude of electric and magnetic field respectively
(e)
The force exerted on the surface.
Answer to Problem 72P
The force exerted on the surface is
Explanation of Solution
Write the expression to calculate the force exerted on the surface.
Here, F is the force and A is the area.
Write the expression to calculate the area.
Use the above equation to rewrite the equation for F.
Conclusion:
Substitute
Thus, the force exerted on the surface is
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Chapter 24 Solutions
Principles of Physics: A Calculus-Based Text
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