Treat the surface of the sun as a perfect blackbody at a temperature of 580OOK. According to Planck's distribution law, what is the ratio of the intensity of the radiation emitted by the sun in the high-energy end of the visible spectrum (around 380nm) compared to that emitted in the low-energy end (around 680nm)?

For light with a wavelength of 350 nm and with an intensity of /= 10-8 W/m², what is the number of photons/(m²s) in the light beam?

A blackbody is brightest at a wavelength of 800 nm. At what wavelength would the blackbody be brightest if its temperature were tripled?

What is the wavelength of a photon emitted when an electron jumps from the n=3 to the n=2 energy levels of a lithium atom (Z=3)? Express your answer in nanometers and keep three significant digits.

Calculate the energy of a photon of frequency 3.5 x 1015 Hz, in electronvolts (eV). Do an online search to find the conversion factor between electronvolts and joules.

Unexcited hydrogen atoms are bombarded with electrons that have been accelerated through 12.5 V. What is the highest energy level that the hydrogen atoms will be excited to? When the electron of the hydrogen atom is excited into the level in part a), what wavelength(s) is (are) possible for the photon emitted when the electron drops to a lower energy level? [Answer in 3 significant figures] a) b)