Explain why the entropy of the universe increases in all real processes?e
Takondwa kaunga , 6 Years ago
Grade 12th pass
Thermal Physics> Explain why the entropy of the universe i...
1 Answers
Arun
Last Activity: 6 Years ago
Mathematical explanation:
Entropy is the ratio of measurable heat change and the absolute temperature, i.e., ΔS=ΔQ/T= (ΔQ) ÷ T
Consider the two different kinds of processes:
1. Reversible process (All intermediates states are in equilibrium):
Let the system absorb heat 'q' from its surroundings.
ΔS(system)=(+q)/T
ΔS(surroundings)= (-q)/T
[Note that the temperatures of both remain same, as there is a constant equilibrium state. Minus sign indicates loss of heat.]
ΔS(total)=ΔS(system)+ΔS(surroundings)=0
2. Irreversible process: Consider the system at a higher temperature T1 and the surroundings at a lower temperature T2. Since heat flows from a system at higher temperature to a system at lower temperature in an irreversible, natural process. If the system loses heat q to the surroundings,
ΔS(system)=(-q)/T1
ΔS(surroundings)= (+q)/T2
ΔS(total)=ΔS(system)+ΔS(surroundings)={q (T1-T2)} ÷ T1T2
Since T1>T2, therefore, T1-T2>0
Therefore, ΔS(process)>0
Hence, whichever process may take place, the system shall always experience an increase in entropy. (Note that the reversible reactions don't add to entropy. Most irreversible processes are favored by all laws and they increase stability.)
Theoretical explanation:
Entropy is simply a mathematical manifestation of disordering. In other words, at a particular temperature, the extent of disordering is explained by entropy (this explains the term ΔQ in the formula). At higher temperature, the same change of heat (ΔQ) causes lesser disordering (this explains inverse variation of ΔS with T). Any feasible and spontaneous process causes disorder in the previous configuration and hence, the entropy increases.
For instance, on connecting two flasks, one of which contains a gas and the other is empty, we find that the molecules of the gas have occupied both flasks to achieve a more probable distribution and entropy increases. Such a probability distribution, by default, is the most observed and hence, more stable.
Entropy is the ratio of measurable heat change and the absolute temperature, i.e., ΔS=ΔQ/T= (ΔQ) ÷ T
Consider the two different kinds of processes:
1. Reversible process (All intermediates states are in equilibrium):
Let the system absorb heat 'q' from its surroundings.
ΔS(system)=(+q)/T
ΔS(surroundings)= (-q)/T
[Note that the temperatures of both remain same, as there is a constant equilibrium state. Minus sign indicates loss of heat.]
ΔS(total)=ΔS(system)+ΔS(surroundings)=0
2. Irreversible process: Consider the system at a higher temperature T1 and the surroundings at a lower temperature T2. Since heat flows from a system at higher temperature to a system at lower temperature in an irreversible, natural process. If the system loses heat q to the surroundings,
ΔS(system)=(-q)/T1
ΔS(surroundings)= (+q)/T2
ΔS(total)=ΔS(system)+ΔS(surroundings)={q (T1-T2)} ÷ T1T2
Since T1>T2, therefore, T1-T2>0
Therefore, ΔS(process)>0
Hence, whichever process may take place, the system shall always experience an increase in entropy. (Note that the reversible reactions don't add to entropy. Most irreversible processes are favored by all laws and they increase stability.)
Theoretical explanation:
Entropy is simply a mathematical manifestation of disordering. In other words, at a particular temperature, the extent of disordering is explained by entropy (this explains the term ΔQ in the formula). At higher temperature, the same change of heat (ΔQ) causes lesser disordering (this explains inverse variation of ΔS with T). Any feasible and spontaneous process causes disorder in the previous configuration and hence, the entropy increases.
For instance, on connecting two flasks, one of which contains a gas and the other is empty, we find that the molecules of the gas have occupied both flasks to achieve a more probable distribution and entropy increases. Such a probability distribution, by default, is the most observed and hence, more stable.
Provide a better Answer & Earn Cool Goodies
Enter text here...
LIVE ONLINE CLASSES
Prepraring for the competition made easy just by live online class.
Full Live Access
Study Material
Live Doubts Solving
Daily Class Assignments
Ask a Doubt
Get your questions answered by the expert for free
Enter text here...
Other Related Questions on Thermal Physics
A container filled with a sample of an Idea gas at the pressure of 1.5atm. the gas is compressed isothermal ly to one fourth of its original volume. What is the new pressure of the gas?
Thermal Physics
0 Answer Available
Last Activity: 1 Year ago(s)
how do we know the electric field due to an electric dipole of dipole moment P at distance r from the centre of dipole is fiven by .. where theta is angle between p amd r vector..
Thermal Physics
0 Answer Available
Last Activity: 2 Year ago(s)
A A mole of helium gas initially at stp undergoes an isovolumetric process in which its pressure falls to half its initial value. The work done by gas is
Thermal Physics
0 Answer Available
Last Activity: 2 Year ago(s)
Please help me with theanswer of this questionrelated to radiation graph
Thermal Physics
0 Answer Available
Last Activity: 2 Year ago(s)