Chapter 13 - Quantum Physics

Question 1

plank constant value

Answer 1

6.63x10^-34

Question 2

1ev value

Answer 2

1.6 x 10^-19 J

Question 3

1 electron volt

Answer 3

energy transferred when an electron travels through a potential difference of 1v

Question 4

planck constant practical

Answer 4

potential divider to vary p.d
tube over LED
vary p.d
find light
take note of wavelength of light
find threshold p.d.
eV = hc/lamda

Question 5

phototelectron effect

Answer 5

electromagnetic radiation shot at surface of metal and electrons are released from the surface

Question 6

what is work function

Answer 6

minimum energy required to free and electron from the surface of a metal

Question 7

wave-particle duality

Answer 7

every particle can be described as a particle or wave

Question 8

what are photons

Answer 8

discrete packets of energy

Question 9

what is the energy of a photon directly proportional to

Answer 9

frequency of the electromagnetic radiation

Question 10

equation relating work done and charge

Answer 10

W = VQ

Question 11

how to improve accuracy of plank constant value

Answer 11

do practical with different coloured LEDs which emit different wavelength of light

Question 12

evidence for wave-particle duality

Answer 12

can be accelerated and deflected by electric and magnetic fields which is particle behaviour.
can also be made to diffract, which is a property of the behaviour of waves