What potential difference in volt is required to be maintaining between the conducting plates having separation 5 mm so that a small oil drop of mass 1.3 x 10-14 kg with two electron remain stationary?

absorption lines are where light has been absorbed by the atom thus you see a dip in the spectrum whereas.

emission spectra have spikes in the spectra due to atoms releasing photons at those wavelengths.

explanation:

the entire statement is true and correct.  

there's no diagram, nothing is illustrated, and no question is asked.

that would be because of both gravity and friction. so     c

snell's law

refractve index = sin incidence / sin refraction