Republic of the Philippines Cebu Normal University Osmena Blud. Cebu City, 6000 Philippines dege of Computing, Artificial Intelligence and Scienc Telephone No.: (+63 32) 254 6814 local 140 Email: ccais@cnu.edu.ph Website: www.cnu.edu.ph Modern Physics Seatwork # 6 1. Silicon films become better electrical conductors when illuminated by photons with energies of 1.14 ev or greater, an effect called photoconductivity. Which of the following wavelengths of electromagnetic radiation can cause photoconductivity in silicon films? (a) Ultraviolet light with I = 300 nm; (b) red light with I = 600 nm; (c) infrared light with I = 1200 nm; (d) both (a) and (b); (e) all of (a), (b), and (c). 2. During the photoelectric effect, light knocks electrons out of metals. So why don't the metals in your home lose their electrons when you turn on the lights? 3. Most black-and-white photographic film (with the exception of some special-purpose films) is less sensitive to red light than blue light and has almost no sensitivity to infrared. How can these properties be understood on the basis of photons? 4. A photon of green light has a wavelength of 520 nm. Find the photon's frequency, magnitude of momentum, and energy. Express the energy in both joules and electron volts. GCL Centrication Date: 1 February 2021 WORLD'S Recertification dun dida: 34 January 2004 UKAS For verification of the outifone pinas check and type the registration number) WURI UNIVERSITIES WITH REAL IMPACT ISO 9001 5945 QS Registration No. 12018778