Ch 38 Relevant Concept Questions

Ch 38 Relevant Concept Questions - of the atom. 4. Suppose...

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University Physics Young and Freedman Chapter 38 Concept Questions and solutions Chapter 38: Pre-Chapter Question Q: The red light from the Eagle Nebula has a wavelength of 656.3 nm. What happens within a hydrogen atom to emit light of this wavelength? A: An electron drops from n = 3 to n = 2 due to excited electrons. 1. N/A 2. Silicon films become better electrical conductors when illuminated by photons with energies of 1.14 eV or greater, an effect called photo conductivity What range of wavelengths causes photo conductivity in silicon films? 1090 nm or less (use Eq. 38.2). 3. Would it be possible to excite the hypothetical atom in Ex. 38.4 from the ground level to the 1.00 eV level with a 1.50 eV photon? No, the energy must be precisely the difference between the initial and final energy levels
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Unformatted text preview: of the atom. 4. Suppose you repeated Rutherford's scattering experiment using a thin sheet of solid hydrogen in place of gold foil (temperatures below 14.0 K). Would you expect to observe large-angle scattering of alpha particles? No, since the Hydrogen atom is so much lighter than an alpha particle. 5. Many wavelengths in the spectrum of light emitted by excited He+ ions are almost the same as the wavelengths emitted by excited H atoms. Why? Fig. 38.22 shows that H and He+ have similar energy levels, so the corresponding levels have similar energies and wavelength values with regards to photon emission. 6. N/A 7. N/A 8. Does a blackbody at 2000 K emit X-rays? Does it emit radio waves? Yes, but only very little (see Fig. 38.31)....
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This note was uploaded on 04/18/2008 for the course PHYS 0030 taught by Professor Cutts during the Spring '07 term at Brown.

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