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Challenge: Problem 1

This problem is divided for convenience into two parts; but the two parts should be attempted before going on to the RESPONSE ARRAY.

(a) The items:

E = T ( a form of the Stefan-Boltzmann law )

and

max T = constant ( Wien's displacement law )

on the RESPONSE ARRAY are accurate only for black-body radiation. Select those items which in some way indicate radiation which could be described by these two items.

(b) In item 1 we have a statement about the number of antinodes in a given frequency interval . If you take into account the "microscopic" aspect of radiation, can you find other items which-on quite different grounds to those belonging to part (a) - are incompatible with the behaviour of black-body radiation?

1
the number of antinodes in the range v to v + dv is ( ( 8 v2 ) / c3 ) dv 		2
radiation pressure p = 1/3 u where u is the energy density		 3
E = T 4 (a form of the Stefan-Boltzmann law)		 4
max T = constant (Wien's displacement law)		 5
fluctuations of energy
6
the energy distribution of radiation is not a function of temperature alone		 7
characteristic vibrational frequency of a material particle's energy state		 8
exchanges of energy in discrete amounts		 9
spectrum of ionized gas		 10
continuum of energy changes
11
one-way emission of radiation		 12
av < 1 (absorbtivity less than one)		 13
a coloured surface often emits its complementary colour when heated		 14
characteristic radiation pattern of a surface for a given temperature		 15
as T decreases below a certain value for a solid, so does its specific heat
16
monochromatic radiation, as obtained by using a filter		 17
= ( hv / ( e ( h v / k T ) - 1 ) )		 18
= n 0		 19
= hv		 20
= kT