topic 1

Question 1

hooks law

Answer 1

F= -KX

Question 2

frequency doesn’t depend on

Answer 2

amplitude

Question 3

• simple harmonic oscillator

Answer 3

• assume at V=0 x=0 total energy = 1/2kA^2
• Amplitude can take any value energy is continuos
• trajectory can be specified

Question 4

features of classic mechanics 1

Answer 4

• predicts trajectory
• position, velocity (therefore momentum) can be known simultaneously
• all vector quantities

Question 5

features of classical mechanics 2

Answer 5

particles and waves are distinguishable, have diff characteristics properites and behaviours

Question 6

features of classical mechanics 3

Answer 6

• any type of motion (translation, vibration, rotation) can have any value of energy associated with it

Question 7

plancks solution to black body

Answer 7

• energy can be absorbed or emitted in small packets which are multiples of frequency
• E = nhv n is intergers

Question 8

blackbody radition

Answer 8

• if object heated it will emit broad range of frequencys
• main emitted wavelength decreases as temp the object is heated to increases causes red hot glow
• black body = perfect absorber

Question 9

photoelectric effect

Answer 9

• metals irradiated with light of diff frequencies, electrons may be ejected
• no electrons ejected, regardless intensity, unless frequency exceeds min
• kinetic energy of ejected electrons is linearly proportional to frequency of incident light
• electrons ejected immediatley if frequency above threshold frequency (Vo)

Question 10

work function

Answer 10

= h x threshold frequencies

Question 11

maximum kinetic energy of an electron

Answer 11

= energy of photon - work function
1/2mv^2 = hv - wf
- if photon energy less than work function therefore no electrons released

Question 12

heat capacities

Answer 12

• relates rise in energy of material with its rise in temp
  Cv = (dU/dT)v
• at low T, heat capacity of solids is determined by vibrations of solids

Question 13

heat capacity deviations from classical physics

Answer 13

• classical physics predicts Cv,m = 3R (for all T)
• experimental = Cv,m less than 3R (C decrease as t decreases)
• overcome by adapting planks constant, new equation based on vibrational energy in solids is quantized