What causes a bolt of lightning?
question options:
electrical charges build up in the clouds.
electrical charges build up on the ground.
electrical charges build up in the clouds and on the ground.
electrical charges build up in the space between the clouds and the ground.

Hydrogen atoms are excited by a laser to the =4n=4 state and then allowed to emit. what is the maximum number of distinct emission spectral lines (lines of different wavelengths) that can be observed from this system? 8 6 2 7 4 5 1 3 calculate the wavelength of the 4⟶14⟶1 transition. =λ=