Planck's Quantum Theory

Question 1

Planck’s Quantum Theory

Answer 1

• Radiation sub divided into discrete quantity of energy (Quantum)
• Emission and Absorption of energy happen in discrete quantities of quanta (i.e. not in continuous manner)
• Energy of each quantum directly proportional to frequency

Question 2

Energy of each quantum

Answer 2

E = h X frequency
where h -> planck’s constant (6.626 X 10^-34 J/s)rtyu

Question 3

Total Energy absorbed

Answer 3

E = n X h X frequency

n = no. of quanta absorbed/emitted

Question 4

Photoelectric effect Definition

Answer 4

Electrons ejected when metal surface irradiated with beam of light

Question 5

Photoelectric effect Observations

Answer 5

• No time lag between photoelectron and beam of light
• No. of electrons ejected proportional to intensity of light
• Each metal has characteristic low frequency (threshold frequency) to eject electron