APPLIED THERMODYNAMICS

1

(MUET SZAB CAMPUS KHAIRPUR MIR’S)

PRESENTATION 01

AKASH Thahrani

K-13ME 05

An office worker claims that a cup of cold coffee on his table warmed up to 80̊̊̊̊̊̊̊̊̊̊̊̊̊̊��

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°C by picking up energy from the surrounding air, which is at 25̊̊̊̊̊̊̊̊̊̊̊̊̊̊��

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°C. Is there any truth to his claim? Does this process violate

any thermodynamics law?

Everything is mentioned over here that, A cold cup of coffee on a table and the surrounding air temperature is 25°C.

Coffee does get hot up to 80°C getting energy from surrounding while surrounding temperature is 25°C.

CLAIMS:Obviously this is impossible to cause heat flow from surrounding at 25°C rather coffee become warmed up to 80°C.

Truth: The truth is that heat flow from surrounding

to coffee until up to that quantity both temperature conserves than 2nd law of thermodynamics does go pass.

Violation of thermodynamics:There is violation/ fail of 2nd law of

thermodynamics, which says that;It contains two statements, if single state go fail

obviously 2nd law will become violate.

Statement of 2nd law of thermodynamics:

i. Celsius statement;“It is impossible to cause heat flow from cold body to hot body without the expenditure of energy”

OR“It is impossible to drive a continuous supply of work by cooling a body to a temperature lower then that the coldest of its surrounding”

Example: In refrigerator temperature is very low, it convert the hotness to coldness if we open the refrigerator, it won’t maintain.

ii. Kelvin statement:If we construct a heat engine which

can work containing without sink.Here law of conservation of energy and 2nd

law of thermodynamics fail/ violate/ equilibrium state does not maintain.

‘THANK YOU’