This document summarizes a presentation by the group "THATA" on temperature and the laws of thermodynamics. It introduces the group members and defines heat and temperature. It then explains the first law of thermodynamics as the conservation of energy, the second law as the tendency for energy to disperse from concentrated to diffuse forms, and the zeroth law as the transitive property of thermal equilibrium between objects at the same temperature. Diagrams illustrate isobaric and isothermal processes and the calculation of work done.

1. Welcome this presentation

2. GROUP NAME: THATA
GROUP MAMBERS
MD.JOBAYAR SIDDIQUE ID:131-15-2436
MD.KAWSAR HAMID ID:131-15-2223
MD.ILIS BAPPI ID:131-15-2266
M.M SHAHREAR ZICO ID:131-15-2459
MD.MAHAFUZUR RAHAMAN ID:131-15-
2201

3. 3
DEFINITION OF HEAT AND TEMPERATURE
HEAT: We all know that bodies can be heated (increasing
their internal energy) or cooled (losing internal energy).
The energy gained or lost in these processes is heat.
TEMPRATURE: Temperature is the average value of the
kinetic energy of these particles.
OUR PRESENTATION TROPIC IS TEMPERATURE AND LAWS OF
THERMODYNAMICS

4. 4
HEAT TEMPERATURE
1. The heat lost or absorbed
by a body
1.The temperature can’t lost
or absorbed by a body
2. Specific heat is the
property of bodies
2. Specific temperature isn’t
the property of bodies
3.Heat don’t remains
constant
3. Temperature remains
constant

5. 5

 simply states that energy can be neither created nor
destroyed (conservation of energy). Thus power
generation processes and energy sources actually
involve conversion of energy from one form to another,
rather than creation of energy from nothing.
The 1st Law of Thermodyamics

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SECOND LAW OF THERMODYNAMICS
 The Second Law of Thermodynamics states that "in all energy
exchanges, if no energy enters or leaves the system, the
potential energy of the state will always be less than that of
the initial state."
 This is also commonly referred to as entropy.
 Example:
 Energy changes are the driving force of the universe. The
driving force of all energy change is the unstoppable
tendency of energy to flow from high concentrations of
energy to lower concentrations of energy.

7. 7ZEROTH LAW OF THERMODYNAMICS
 The zeroth law of thermodynamics states that if two
systems, A and B, are in thermal equilibrium with a third
system, C, then A and B are in thermal equilibrium with
each other. It is analogous to the transitive property in
math (if A=C and B=C, then A=B). Another way of stating
the zeroth law is that every object has a certain
temperature, and when two objects are in thermal
equilibrium, their temperatures are equal. It is called the
"zeroth" law

8.  ΔU = Q – W
where ΔU is the increase of internal energy of the
system, Q is the heat entering the system, and W is
the work done by the system.
The differential form of the 1st Law is
 dU = dQ – dW,
 where dU is an exact differential, because U is a
state variable, and both dQ and dW are inexact
differentials, since Q and W are not state variables.

9. SECOND LAW OF THERMODYNAMICS
 The entropy of an isolated system never decreases;
 ΔS ≥ 0,
 or, at equilibrium, S → Smax.
 For a reverse Examples of irreversible (real) processes:
 i. temperature equalization;
 ii. mixing of gases;
 iii. conversion of macroscopic (ordered) KE to thermal (random)
 KE.
 ble (idealized) process only,
 ΔS = 0, dS = dQ/T.

10.  Zeroth Law of Thermodynamics
 Two systems, separately in thermal equilibrium with a
third system, are in thermal equilibrium with each other.
 The property which the three systems have in common is
known as temperature θ.
 Thus the zeroth law may be expressed as follows:
 if θ1 = θ2 and θ1 = θ3, then θ2 = θ3.

12. V2V1
P
Isobaric process
W = P(V2 – V1)
Isothermal
process
V2
P
V1
Calculating the work done in a reversible isothermal process requires the equation of state
of the system to be known.
Reversible isothermal process for an ideal gas (PV = nRT)
W = ∫PdV = nRT ∫dV/V = nRT ln(V2/V1).
In both cases, the work done by the system equals the shaded area under curve.

13. • THANK YOU