Quantum

Question 1

Characteristics of electrons

Answer 1

• have mass
• have charge
• gain KE
• can be deflected in E and B fields
• are particles
• display wave behaviour = can be diffracted through graphite

Question 2

Wavelength is inversely proportional to voltage

Answer 2

Faster v = shorter wavelength
Slower v = longer wavelength

Question 3

True or false ?
Electron gun accelerated electron

Answer 3

True

Question 4

How is energy gained ?

Answer 4

1 electron is accelerated through 1 volt

Question 5

Increasing potential difference will have what result

Answer 5

• more acceleration
• more KE
• higher voltage
• shorter wavelength

Question 6

Einsteins proposed particle behaviour

Answer 6

A photon is a quantum of energy of EM radiation

Question 7

Wave behaviour characteristics

Answer 7

• polarised
• no mass
• no charge
• reflected
• refracted
• diffracted

Question 8

What does the photoelectric effect show

Answer 8

When electromagnetic radiation is shone onto a metal, electrons are released from the surface of the metal

Question 9

Explain the gold leaf electroscope

Answer 9

• zinc plate on top of a negatively charged stem with a negatively charged stem, with a negatively charged piece of gold leaf attached to stem
• same charge so repel each-other
• if UV light is shone onto zinc plate, free electrons releases meaning negative charge slowly lost and gold leaf falls back to stem
• even if UV has low intensity electrons are stil instantaneously removed

Question 10

Work function

Answer 10

Minimum energy required to free an electron

Question 11

De briglie equation explains what

Answer 11

• all matter can exhibit both wave and particle properties
• wavelength associated with particle is inversely proportional to momentum
• as mass of particle increases, wavelength decreases, so harder to observe wave like properties

Question 12

What is a photon

Answer 12

When electromagnetic radiation interacts with matter, it interacts as a discrete energy quanta (packets)