Concept explainers
(a)
The power
(a)
Answer to Problem 8P
The power radiated by the black body is
Explanation of Solution
Write the expression for the power radiated by the black body.
Here,
Conclusion:
Substitute
Thus, the power radiated by the black body is
(b)
The wavelength at which the blackbody radiate most intensely.
(b)
Answer to Problem 8P
The wavelength at which the blackbody radiate most intensely is
Explanation of Solution
Write the equation for the wavelength at which the blackbody radiate most intensely.
Here,
Conclusion:
Substitute
Thus, the wavelength at which the blackbody radiate most intensely is
(c)
The spectral power per wavelength interval at
(c)
Answer to Problem 8P
The spectral power per wavelength interval at
Explanation of Solution
Write the equation for
Here,
Write the equation for
Here,
Write the equation for the power per wavelength interval.
Substitute
Conclusion:
Substitute
Substitute
Substitute
Thus, the spectral power per wavelength interval at
(d)
The spectral power per wavelength interval at
(d)
Answer to Problem 8P
The spectral power per wavelength interval at
Explanation of Solution
From the equation (V) in part (c), the spectral power per wavelength is.
Conclusion:
Substitute
Thus, the spectral power per wavelength interval at
(e)
The spectral power per wavelength interval at
(e)
Answer to Problem 8P
The spectral power per wavelength interval at
Explanation of Solution
From the equation (V) in part (c), the spectral power per wavelength is.
Conclusion:
Substitute
Thus, the spectral power per wavelength interval at
(f)
The spectral power per wavelength interval at
(f)
Answer to Problem 8P
The spectral power per wavelength interval at
Explanation of Solution
From the equation (V) in part (c), the spectral power per wavelength is.
Conclusion:
Substitute
Thus, the spectral power per wavelength interval at
(g)
The spectral power per wavelength interval at
(g)
Answer to Problem 8P
The spectral power per wavelength interval at
Explanation of Solution
From the equation (V) in part (c), the spectral power per wavelength is.
Conclusion:
Substitute
Thus, the spectral power per wavelength interval at
(h)
The spectral power per wavelength interval at
(h)
Answer to Problem 8P
The spectral power per wavelength interval at
Explanation of Solution
From the equation (V) in part (c), the spectral power per wavelength is.
Conclusion:
Substitute
Thus, the spectral power per wavelength interval at
(I)
The spectral power per wavelength interval at
(I)
Answer to Problem 8P
The spectral power per wavelength interval at
Explanation of Solution
From the equation (V) in part (c), the spectral power per wavelength is.
Conclusion:
Substitute
Thus, the spectral power per wavelength interval at
(J)
The power radiated by the object as visible light.
(J)
Answer to Problem 8P
The power radiated by the object as visible light is
Explanation of Solution
The wavelengths
Write the equation for the power radiated.
Here,
Conclusion:
The average power is calculated from the visible area.
Substitute
Thus, the power radiated by the object as visible light is
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Chapter 39 Solutions
Physics for Scientists and Engineers with Modern Physics
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- A pulsed ruby laser emits light at 694.3 nm. For a 14.0-ps pulse containing 3.00 J of energy, find (a) the physical length of the pulse as it travels through space and (b) the number of photons in it. (c) Assuming that the beam has acircular cross-section of 0.600 cm diameter, find the number of photons per cubic millimeter.arrow_forwardSuppose that the microwave radiation has a wavelength of 11.6 cm. How many photons are required to heat 265 mL of coffee from 25.0 degrees Celcius to 62.0 degrees Celcius? Assume that the coffee has the same density, 0.997 g/mL, and specific heat capacity, 4.184 J/(g.K), as water over this temperature range.arrow_forwardHow many photons with a wavelength of 450 nm is required to have a mass of 1.25 micrograms?arrow_forward
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