Constants: h=6.626times 10^-34Js, q=1.6times 10^-19C, c=3times 10^8m/s 1. A single photon in free space has wavelength of 0.4mu m 1.A. Its frequency in Hertz (Hz) is __ (30 puan) a. 1.2times 10^8Hz b 1.2times 10^14Hz C. 7.5times 10^14Hz d. 1.6times 10^8Hz 1.B. Its energy in electron volts (eV) is __ (30 puan) là. 4.96 eV b. 1.77 eV IC. 0.177 eV d. 3.1 eV . Based on the relationship between photon energy and wavelength, a useful guideline is that E(in electron volts)=K/n where lambda is expressed in nanometers . The value of K is __ (40 puan) I a. 2.208 b. 1243 IC. 1.243 d. 2208

1.A. The frequency of a photon can be calculated using the equation , where is the speed of light, is the wavelength, and is the frequency. Rearranging the equation, we have . Plugging in the given values, we have . Therefore, the correct answer is option c.1.B. The energy of a photon can be calculated using the equation , where is Planck's constant and is the frequency. Plugging in the given values, we have . To convert this energy to electron volts, we divide by the charge of an electron ( ), resulting in . Therefore, the correct answer is option d.The value of K in the equation is the energy in electron volts when is expressed in nanometers. This relationship is derived from the equation , where . Rearranging this equation, we have . Since and are constants, the value of K is equal to , which is . Therefore, the correct answer is option b.