Modern Physics for Scientists and Engineers
4th Edition
ISBN: 9781133103721
Author: Stephen T. Thornton, Andrew Rex
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 3, Problem 25P
To determine
The ultraviolet catastrophe can be avoided for short wavelengths in the Planck’s
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Radiation has been detected from space that is characteristic of an ideal radiator at T = 2.728 K. (This radiation is a relic of the Big Bang at the beginning of the universe.) For this temperature, at what wavelength does the Planck distribution peak? In what part of the elec- tromagnetic spectrum is this wavelength?
For the thermal radiation from an ideal blackbody radiator with a surface temperature of 2000 K, let Ic represent the intensity per unit wavelength according to the classical expression for the spectral radiancy and IP represent the corresponding intensity per unit wavelength according to the Planck expression.What is the ratio Ic/IP for a wavelength of (a) 400 nm (at the blue end of the visible spectrum) and (b) 200 mm (in the far infrared)? (c) Does the classical expression agree with the Planck expression in the shorter wavelength range or the longer wavelength range?
For a temperature of 5800 K (the sun's surface temperature), find the wavelength for
which the spectral distribution calculated by the Planck and Rayleigh-Jeans results differ
by 5%.
Hint: To match the required condition consider:
IR-J = 1.05 I
Chapter 3 Solutions
Modern Physics for Scientists and Engineers
Ch. 3 - Prob. 1QCh. 3 - Prob. 2QCh. 3 - Prob. 3QCh. 3 - Prob. 4QCh. 3 - Prob. 5QCh. 3 - Prob. 6QCh. 3 - Prob. 7QCh. 3 - Prob. 8QCh. 3 - Prob. 9QCh. 3 - In the experiment of Example 3.2, how could you...
Ch. 3 - Prob. 11QCh. 3 - Prob. 12QCh. 3 - Prob. 13QCh. 3 - Prob. 14QCh. 3 - Prob. 15QCh. 3 - Prob. 16QCh. 3 - Prob. 17QCh. 3 - Prob. 18QCh. 3 - Prob. 19QCh. 3 - Prob. 20QCh. 3 - Prob. 21QCh. 3 - Prob. 22QCh. 3 - Prob. 23QCh. 3 - Prob. 24QCh. 3 - Prob. 25QCh. 3 - Prob. 26QCh. 3 - Prob. 1PCh. 3 - Prob. 2PCh. 3 - Across what potential difference does an electron...Ch. 3 - Prob. 4PCh. 3 - Prob. 5PCh. 3 - Prob. 6PCh. 3 - Prob. 7PCh. 3 - Prob. 8PCh. 3 - Prob. 9PCh. 3 - Prob. 10PCh. 3 - Prob. 11PCh. 3 - Prob. 12PCh. 3 - Prob. 13PCh. 3 - Prob. 14PCh. 3 - Prob. 15PCh. 3 - Prob. 16PCh. 3 - Calculate max for blackbody radiation for (a)...Ch. 3 - Prob. 18PCh. 3 - Prob. 19PCh. 3 - Prob. 20PCh. 3 - White dwarf stars have been observed with a...Ch. 3 - Prob. 22PCh. 3 - Prob. 23PCh. 3 - Prob. 24PCh. 3 - Prob. 25PCh. 3 - Prob. 26PCh. 3 - Prob. 27PCh. 3 - Prob. 32PCh. 3 - Prob. 33PCh. 3 - Prob. 34PCh. 3 - Prob. 35PCh. 3 - Prob. 36PCh. 3 - Prob. 37PCh. 3 - Prob. 38PCh. 3 - Prob. 39PCh. 3 - Prob. 40PCh. 3 - Prob. 41PCh. 3 - Prob. 42PCh. 3 - Prob. 43PCh. 3 - Prob. 44PCh. 3 - Prob. 45PCh. 3 - Prob. 46PCh. 3 - Prob. 47PCh. 3 - Prob. 48PCh. 3 - Prob. 49PCh. 3 - Prob. 50PCh. 3 - Prob. 52PCh. 3 - Prob. 53PCh. 3 - Prob. 54PCh. 3 - Prob. 55PCh. 3 - Prob. 56PCh. 3 - Prob. 57PCh. 3 - Prob. 58PCh. 3 - Prob. 59PCh. 3 - Prob. 60PCh. 3 - Prob. 61PCh. 3 - Prob. 62PCh. 3 - Prob. 63PCh. 3 - Prob. 64PCh. 3 - Prob. 65PCh. 3 - Prob. 66PCh. 3 - Prob. 67PCh. 3 - Prob. 68PCh. 3 - The Fermi Gamma-ray Space Telescope, launched in...Ch. 3 - Prob. 70P
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.Similar questions
- A) Calculate the de Broglie wavelength of a neutron (mn = 1.67493×10-27 kg) moving at one six hundredth of the speed of light (c/600). Enter at least 4 significant figures. (I got the answer 949.4 pm but it is wrong, please help) B) Calculate the velocity of an electron (me = 9.10939×10-31 kg) having a de Broglie wavelength of 230.1 pm.arrow_forwardLet's say that a photon carries an energy equivalent to 620 eV (electron volts). Knowing that h*c = 1240 eV*nm, what type of radiation is this photon?arrow_forwardWhen an electron is accelerated through a potential difference Δφ it acquires a kinetic energy e Δφ. Calculate the momentum, and hence the de Broglie wavelength, of an electron accelerated from rest through (a) 1.00V, (b) 1.00 kV, (c) 100 kV.arrow_forward
- Consider a black body of surface area 22.0 cm² and temperature 5700 K. (a) How much power does it radiate? 131675.5 W (b) At what wavelength does it radiate most intensely? 508.421 nm (c) Find the spectral power per wavelength at this wavelength. Remember that the Planck intensity is "intensity per unit wavelength", with units of W/m³, and "power per unit wavelength" is equal to that intensity times the surface area, with units of W/m 131.5775 Your response differs significantly from the correct answer. Rework your solution from the beginning and check each step carefully. W/marrow_forwardCalculate the De-Broglie wavelength for, A biological virus of size d is 10 nm – 300 nm, mass m is 10 ^ -15 kg and average speed v = 1 mm/s. An atomic electron size of d is 2.8 fm, mass m is 9.1 x 10^-31 kg, and in orbital speed in first Bohr orbit is v= 2.6 x 10^6 m/sarrow_forwardAssume we have a material with a work function of 4.94 eV. What is the maximum speed, in meters per second, of electrons ejected from this metal by photons of light with wavelength 75 nm?arrow_forward
- A proton with total energy 5.52 keV, and initial de Broglie wavelength λi travels from a region with no potential energy to a region with potential energy 1.51 keV where it has a de Broglie wavelength λf. What is the de Broglie wavelength ratio λf/λi, i.e. the relative change in wavelength?arrow_forwardIn a photoelectric experiment it is found that a stopping potential of 1.00 V is needed to stop all the electrons when incident light of wavelength 225 nm is used and 1.5 V is needed for light of wavelength 207 nm. From these data determine Planck's constant. (Enter your answer, in eV s, to at least four significant figures.) 4.2367e-15 X ev s From these data determine the work function (in eV) of the metal. 4.6 X evarrow_forwardWhen an electron is accelerated through a potential difference Δφ it acquires a kinetic energy eΔφ. Calculate the momentum, and hence the de Broglie wavelength, of an electron accelerated from rest through (a) 1.00 V. (b) 1.00 kV. (c) 100 kVarrow_forward
- A blackbody is an object with a radiation spectrum that is dependent solely on its tempera- ture. A blackbody spectrum (or spectral radiancy curve) is described by the Planck Radiation Law. (a) i. Sketch the spectral radiancy curves for blackbodies with temperatures of T = 4000 K and T = 6000 K, respectively. Describe the main differences between the two curves in terms of the appropriate physical laws defined as a function of tempera- ture. ii. What is the wavelength at peak intensity for each blackbody? State the part of the electromagnetic spectrum to which each wavelength belongs. (b) Use the Planck Radiation Law to determine the power radiated per unit area between the wavelengths A 500 nanometres and λ = 503 nanometres for the T 6000 K blackbody. What fraction of the blackbody's radiancy lies in this wavelength range? =arrow_forwardThrough what potential difference ΔVΔV must electrons be accelerated (from rest) so that they will have the same wavelength as an x-ray of wavelength 0.130 nmnm? Use 6.626×10−34 J⋅sJ⋅s for Planck's constant, 9.109×10−31 kgkg for the mass of an electron, and 1.602×10−19 CC for the charge on an electron. Express your answer using three significant figures. =89.0 V Through what potential difference ΔVΔV must electrons be accelerated so they will have the same energy as the x-ray in Part A? Use 6.626×10−34 J⋅sJ⋅s for Planck's constant, 3.00×108 m/sm/s for the speed of light in a vacuum, and 1.602×10−19 CC for the charge on an electron. Express your answer using three significant figures. Second question is what I need help on! Thanks!arrow_forwardIn an experiment on the photoelectric effect, a metal is illuminated by visible light of different wavelengths. A photoelectron has a maximum kinetic energy of 0.9 eV when red light of wavelength 640 nm is used. With blue light of wavelength 420 nm, the maximum kinetic energy of the photoelectron is 1.9 eV. Use this information to calculate an experimental value for the Planck constant h. [arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Physics for Scientists and Engineers with Modern ...PhysicsISBN:9781337553292Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningModern PhysicsPhysicsISBN:9781111794378Author:Raymond A. Serway, Clement J. Moses, Curt A. MoyerPublisher:Cengage Learning
Physics for Scientists and Engineers with Modern ...
Physics
ISBN:9781337553292
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Modern Physics
Physics
ISBN:9781111794378
Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer
Publisher:Cengage Learning