And: glass amplifier material has peak emission cross section 4 × 10–20 cm2 at the amplifier wavelength = 1054 nm, and fluorescence lifetime 290 s. the nd ion density is 3 × 1020 cm–3, and the pump rate for one nd ion is 170 s–1. (a) determine the number of nd ions pumped to the excited state per unit volume per unit time. (b) if there is no signal light, determine the steady-state, upper-level population (number of excited ions per unit volume). (c) what fraction of nd ions are in the excited state? (d) determine the gain coefficient at 1054 nm.

The experiment was repeated many years later but the gases were mixed in a different type of container. a white solid was obtained which was xenon fluoride. predict whether you think 1) krypton and 2) radon will react with fluorine. explain reasons for your predictions

What characteristics of hv2112 make it the best candidate to be classified as a thorne-zytkow object?

You are still fascinated by the process of inkjet printing, as described in the opening storyline for this chapter. you convince your father to take you to his manufacturing facility to see the machines that print expiration dates on eggs. you strike up a conversation with the technician operating the machine. he tells you that the ink drops are created using a piezoelectric crystal, acoustic waves, and the plateau-rayleigh instability, which creates uniform drops of mass m = 1.25 ✕ 10−8 g. while you don't understand the fancy words, you do recognize mass! the technician also tells you that the drops are charged to a controllable value of q and then projected vertically downward between parallel deflecting plates at a constant terminal speed of 20.0 m/s. the plates are ℓ = 2.15 cm long and have a uniform electric field of magnitude e = 6.40 ✕ 104 n/c between them. noting your interest in the process, the technician asks you, "if the position on the egg at which the drop is to be deposited requires that its deflection at the bottom end of the plates be 0.17 mm, what is the required charge on the drop (in c)? " you quickly get to work to find the answer. (neglect the force of gravity.)