An electron was ejected from a sodium metal surface with 6.8 x 10¹⁴ s⁻¹ radiation. What is the (minimum) wavelength (in nm) of the ejected electron? The work function of sodium is 2.50 x 10⁻¹⁹ J.

A laser pointer used in the classroom emits light at 4950 Å, at a power of 4.00 mW. (One watt is the SI unit of power, the measure of energy per unit of time. 1 W = 1 J/s). How many photons are emitted from the pointer in 115 seconds?

Silver has a work function, Φ, of 4.64 eV. If a sample of silver is bombarded with 213 nm photons, what will be the wavelength (in meters) of the photo-ejected electrons? (1 eV = 1.60 × 10⁻¹⁹ J, the mass of an electron is 9.109 x 10⁻³¹ kg, and Planck's constant is 6.626 x 10⁻³⁴ Js.)

Using the Bohr model of an electron orbiting a nucleus, the angular momentum of Earth's orbit around the Sun is about 2.67 x 1040 g m2 s−1. Using the Bohr quantization condition, what is the quantum number n for Earth's orbit? If the Earth transitions from this orbit to n-1 (emitting a graviton, which is the gravitational anagloue of the photon), how much energy would be released? Find the frequency of the graviton.