Optical phenomena and properties of materials

Question 1

Photoelectric effect

Answer 1

The process whereby electrons are ejected off the surface of a metal when light of suitable frequency is incident on that surface

Question 2

Threshold frequency

Answer 2

minimum frequency of light needed to emit electrons from a certain metal surface

Question 3

Work function

Answer 3

minimum energy that an electron in the metal needs to emitted from the surface of the metal

Question 4

Continuous emission spectrum

Answer 4

shows all possible wavelengths of light in the visible part of the electromagnetic spectrum

Question 5

Line emission spectrum

Answer 5

Emitted by hot gases under low pressure where electrons make transitions from higher energy levels to lower energy levels. Photons of specific energies emitted

Question 6

Line absorption spectrum

Answer 6

When white light passes through a cold gas at low pressure. Electrons make transitions from low energy levels to high energy levels. Photons of specific energies absorbed.