EM Radition and Quantum Phenomena Flashcards Preview

A-Level Physics > EM Radition and Quantum Phenomena > Flashcards

Flashcards in EM Radition and Quantum Phenomena Deck (18)
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1
Q

Energy carried by a photon

A

E = hf = hc/λ

2
Q

Threshold frequency

A

f = φ/h

3
Q

How to find the maximum kinetic energy

A

hf = φ + Ek(max)

4
Q

De Broglie wavelength

A

λ = h/mv

5
Q

What is the work function of a metal

A

Energy required to break bonds holding electron to the metal’s surface

6
Q

What is the stopping potential

A

The pd needed to stop the fastest moving electron

7
Q

How does intensity of radiation relate to no of electrons emitted

A

Directly proportional

8
Q

What shows light as a wave

A

Interference and diffraction

9
Q

What shows light as a particle

A

Photoelectric effect

10
Q

What did de Broglie suggest

A

If wave-like light showed particle properties, electrons should show wave-like properties

11
Q

How to prove wave nature of electrons

A

Diffraction patterns are observed when accelerated electrons in a vacuum tube interact with spaces in a graphite crystal

12
Q

Does larger wavelength reduce or increase spread of lines in a diffraction pattern

A

Increase spread of lines

13
Q

What does it mean if an atom is ionised

A

Has lost an electron

14
Q

What is the ionisation energy of an atom

A

The energy needed to remove an electron from an atom from the ground state (n=1)

15
Q

Define the elecronvolt

A

The KE carried by an electron after it has been accelerated through a potential difference of 1 volt

16
Q

Define excitation

A

When an electron moves to a higher energy level

17
Q

How to convert eV to J

A

x 1.6e-19

18
Q

Formula for stopping potential

A

eVs = KEmax