A certain atom has only three energy levels. From lowest to highest energy, these levels are denoted n = 1, n = 2, and n = 3. When the atom transitions from the n = 3 level to the n = 2 level, it emits a photon of wavelength 800 nm. When the atom transitions from the n = 2 level to the n = 1 level, it emits a photon of wavelength 200 nm. What is the wavelength of the photon emitted when the atom transitions from the n = 3 level to the n = 1 level?A. 1000 nm B. 600 nm
C. 500 nm
D. 160 nm

Athin nonconducting rod with a uniform distribution of positive charge q is bent into a circle of radius r. the central perpendicular axis through the ring is a z-axis, with the origin at the center of the ring. a) what is the magnitude of the electric field due to the rod at z = 0? n/c (b) what is the magnitude of the electric field due to the rod at z = infinity? n/c (c) in terms of r, at what positive value of z is that magnitude maximum? r (d) if r = 4.00 cm and q = 9.00 µc, what is the maximum magnitude? n/c