1. 2. Assume the Sun can be treated like an ideal blackbody at 5778 K. (a) What is the intensity of radiation emitted in the range of 496 nm to 498 nm? Hint: Use Planck's intensity distribution: 211hc 2 ehc/XkT 1' and assume the intensity is approximately constant over this small range of wavelengths. (b) What fraction of the total solar radiation intensity does this represent? When sodium metal is illuminated with 420 nm light, the stopping potential is found to be 0.65 V. When the wavelength is changed to 310 nm, the stopping potential is 1.69 V. Using only these two data points find the work function of sodium and a value of Planck's constant.