Modern Physics

Question 1

What is an ELECTRON?

Answer 1

An ELECTRON is a sub-atomic particle that orbits the nucleus. It has a mass of 9.1 x10¯³¹ kg and a charge of 1.6 x10¯¹⁹ C which is the fundamental frequency of charge

Question 2

What is THERMIONIC EMISSION?

Answer 2

THERMIONIC EMISSION is the release of electrons from the surface of a hot metal

Question 3

What are CATHODE RAYS?

Answer 3

CATHODE RAYS are streams of high-speed electrons moving from the cathode to the anode in an evacuated tube

Question 4

What is the PHOTOELECTRIC EFFECT?

Answer 4

The PHOTOELECTRIC EFFECT is the release of electrons from the surface of a metal when UV light of a certain frequency is shone on it

Question 5

What is the THRESHOLD FREQUENCY (f₀)?

Answer 5

The THRESHOLD FREQUENCY (f₀) for a given metal is the minimum frequency needed for photoemission to occur

Question 6

What is the WORK FUNCTION (Φ)

Answer 6

The WORK FUNCTION (Φ) of a metal is the minimum amount of energy required by a photon to remove an electron from the surface of the metal

Question 7

What are X-RAYS?

Answer 7

X-RAYS are high frequency electromagnetic radiation which are produced when high-speed electrons strike a metal target of high melting point