Can Macroscopically Distinguishable Objects Have the Same Entropy?

  • Thread starter Thread starter shimzz5
  • Start date Start date
  • Tags Tags
    Entropy
AI Thread Summary
Entropy measures the disorder or distinguishability of macroscopic states, and it is possible for macroscopically distinguishable objects to have the same entropy despite differing atomic structures. The discussion highlights that while objects like a house and a football are distinguishable, their entropy is not necessarily affected by this distinction. Two objects, such as balls of the same volume but different colors, can have the same entropy, as entropy is a single-dimensional variable while macroscopic appearance is multi-dimensional. The concept of Boltzmann entropy, which relates to the number of microstates, is central to understanding this phenomenon. Ultimately, macroscopic distinguishability does not preclude identical entropy values.
shimzz5
Messages
4
Reaction score
1
I'm kinda confused on the concept of entropy of everyday, low entropy states like macroscopic objects. It is said that the entropy is a measure of disorder, or distinguishability between macroscopic states.

Can two objects which are macroscopically distinguishable/look different have the same entropy, despite the fact that their atomic structure/configuration is different? Or the only states which can possesses the same entropy are completely indistinguishable macroscopically?

Thanks in advance.
 
Science news on Phys.org
What definition of entropy are you using?

A house and a football are distinguishable, but I wouldn't say that's to do with having different entropy, per se.
 
The Boltzmann entropy -the number of microstates.

We can imagine two balls of the same volume but which are macroscopically different - can they have the same entropy?
 
shimzz5 said:
The Boltzmann entropy -the number of microstates.

We can imagine two balls of the same volume but which are macroscopically different - can they have the same entropy?
Yes, obviously. Entropy is a single variable. One dimension. Macroscopic appearance is multi-dimensional.

Consider a red ball on the one hand and a green ball on the other. Either they already have the same entropy or one can be adjusted in size to have the same entropy as the other.
 
  • Like
Likes vanhees71
I need to calculate the amount of water condensed from a DX cooling coil per hour given the size of the expansion coil (the total condensing surface area), the incoming air temperature, the amount of air flow from the fan, the BTU capacity of the compressor and the incoming air humidity. There are lots of condenser calculators around but they all need the air flow and incoming and outgoing humidity and then give a total volume of condensed water but I need more than that. The size of the...
Thread 'Why work is PdV and not (P+dP)dV in an isothermal process?'
Let's say we have a cylinder of volume V1 with a frictionless movable piston and some gas trapped inside with pressure P1 and temperature T1. On top of the piston lay some small pebbles that add weight and essentially create the pressure P1. Also the system is inside a reservoir of water that keeps its temperature constant at T1. The system is in equilibrium at V1, P1, T1. Now let's say i put another very small pebble on top of the piston (0,00001kg) and after some seconds the system...
Back
Top