ThermodynamicsHard
Question
Suppose the sun expands so that its radius becomes 100 times its present radius and its surface temperature becomes half of its present value. The total energy emited by it then will increase by a factor of :
Options
A.104
B.625
C.16
D.16
Solution
E = σT4, here E is energy radiated per area. Total energy emitted = σT4 × A Total energy emitted by sun after expansion
σ ×
× 100 × 100 A [where radius becomes 100 times,area becomes 1002 times]
σT4 ×
× 100 × 100 = 625 × σT4A
So, total energy emitted is 625 times.
σ ×
× 100 × 100 A [where radius becomes 100 times,area becomes 1002 times] σT4 ×
× 100 × 100 = 625 × σT4A So, total energy emitted is 625 times.
Create a free account to view solution
View Solution FreeMore Thermodynamics Questions
A thermodynamic system is taken through the cycle ABCDas shown in figure. Heat rejected by the gas during the cycleis...A Carnot engine, whose efficiency is 40% takesin heat from a source maintained at atemperature of 500 K. It is desired t...The plots of intensity versus wavelength for three black bodies at temperature T1, T2 and T3 respectively are as shown. ...A black body has maximum wavelength λm at 2000 K. Its corresponding wavelength at 3000 K is:...In a process, 500 calories of heat is given to a system and at the same time, 100 joules of work is done on the system. ...