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 gas collects in coils that then becomes a liquid that then flows through the coils inside the refrigerator

think its the third option

false br

the order for strong to weak forces such as

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

the fundamental forces are those forces that act between to objects or element to make interactions. there are four types of fundamental forces such as strong and weak nuclear forces (due to protons and electrons), electromagnetic force (due to the motion of electrons) and gravitational force (due to orbital movement of the planet). if these forces are arranged on the basis of their maximum strength then the order is

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force