Helium produces the following atomic emmision spectrum lines 388.8 447.1 471.3 492.1 501.5 504.7 587.5 667.8 686.7 706.5 728.1 781.3 for each of these wavelengths determine the corresponding frequency

Henry, whose mass is 95 kg, stands on a bathroom scale in an elevator. the scale reads 830 n for the first 2.4 s after the elevator starts moving, then 930 n for the next 2.4 s. part a what is the elevator's speed 4.8 s after starting? express your answer with the appropriate units.

Which system of units is used by only a small number of countries in the world, including the u.s.

Adielectric-filled parallel-plate capacitor has plate area a = 30.0 cm2 , plate separation d = 9.00 mm and dielectric constant k = 3.00. the capacitor is connected to a battery that creates a constant voltage v = 15.0 v . throughout the problem, use ϵ0 = 8.85x10-12 c2/n.m2 . find the energy u1 of the dielectric-filled capacitor.