Electromagnetic radiation at temperature t in an enclosure of volume vhas pressure p and energy density u given by и —а т* р 3 1sat" and where a is a constant. (a) write down the ftr and use it to show that as = 4avt2; дт (i) as 4 =-al 3 (ii) ду hint: write e = vu and hence find an expression for de in terms of du and dv; note that uis a function only of t 5 marks] (b) use the results of part (a) to show that the entropy s of the radiation is given by: (i) 4 s = (ii the helmholtz free energy of the radiation is given by f = -pv.

unlike poles attract

answer: at 24 february, 2014 the population gets twice of its initial population.

explanation:

since we have given that

the population for alpha city, t years after january 1, 2004 is given as

first we find out the initial population, i.e. t=0,

so, our quadratic equation becomes,

according to question, we have said that if the population has twice its initial population, then it becomes

so, time taken to reach this above mentioned population is given by

now, we know that time can't be negative so, we take t=9.149 years.

hence, at 24 february, 2014 the population gets twice of its initial population.

490 n

f=125n a=2.5m/s2