8. Compute the ratio of the increase of intensity of black-body radiation at a wavelength of...
7. What is the relation between temperature and intensity of black body radiation? 8. What is the relation between the temperature of a black body and the color of its radiation? 9. What is the closest thing to a black body in our everyday life? 10. What is the importance of Planck's radiation law for modern Physics?
2. The maximum wavelength of an ideal black body cavity radiation absorption is 6000 A. a. If the emission of thermal radiation from the cavity becomes 3 times, then what is the maximum wavelength and temperature? b. If the emission of thermal radiation from the cavity becomes times, then what is the maximum wavelength and temperature?
8. A black body has an effective surface temperature of 450°C. Determine: (a) The total radiation energy (W/m²) that can be emitted by the black body (b) Determine total radiation energy (W/m²) that can be emitted by the black body within the 5-50 um wavelength region (c) The spectral blackbody emissive power of the black body at a wavelength of 10 um.
(1) The intensity of blackbody radiation peaks at a wavelength of 668 nm. (a)What is the temperature (in K) of the radiation source? (Give your answer to at least 3 significant figures.) (b)Determine the power radiated per unit area (in W/m2) of the radiation source at this temperature. (2) What is the binding energy in eV of electrons in ruthenium, if the longest-wavelength photon that can eject electrons is 264 nm?
The intensity of blackbody radiation peaks at a wavelength of 608 nm. (a) What is the temperature (in K) of the radiation source? (Give your answer to at least 3 significant figures.) ______K (b) Determine the power radiated per unit area (in W/m2) of the radiation source at this temperature. _______ W/m2
8. IE (a) If you have a fever, will the wavelength of the radiation component of maximum intensity emitted by your body (1) increase, (2) remain the same, or (3) decrease as compared with its value when your temperature is normal? Why? (b) Assume that human skin has a temperature of 32°C. What is the wavelength of the radiation component of maximum intensity emitted by our bodies? In what region of the EM spectrum is this wavelength?
The transmittance of a sample is the ratio of the intensity of radiation transmitted to the intensity of the incident radiation. The molar absorption coefficient of the [Cu(NH3)4]2+complex ion in aqueous solution is 50 dm3 mol–1 cm–1at a wavelength of 590 nm. Determine the transmittance when light of this wavelength passes through an aqueous solution of the ion of molar concentration 0.100 mol dm–3and path length 1.00 cm.
A black body has an effective surface temperature of 450°C. Determine: (a) The total radiation energy (W/m2) that can be emitted by the black body (b) Determine total radiation energy (W/m%) that can be emitted by the black body within the 5-50 um wavelength region (c) The spectral blackbody emissive power of the black body at a wavelength of 10 um. 12
Use a computer to calculate Planck's radiation law for a temperature of 3000 K, which is the temperature of a typical tungsten filament in an incandescent light bulb. Plot the intensity versus wavelength. (a) How much of the power is in the visible region (400-700nm) compared with the ultraviolet and infrared? (b) What is the ratio of the intensity at 400 nm and 700 nm to the wavelength with maximum intensity?
An oven (considered to be a black body) is at 6000K. a) What is the EM intensity of the oven between the wavelengths of 550nm and 551nm? (Hint: us the average wavelength for .) b) Find the number of photons of this radiation escaping per second through a tiny hole in the oven of radius 0.025mm. (Hint: first find the # of J/sec escaping.)