1. heat

2. The zeroth law of thermodynamics
Thermal contact الأتصال الحراري تبادل الطاقة الحرارية بدون بذل شغل Thermal equilibrium الاتزان الحراري بين جسمين يحدث اذا كان بينهما اتصال حراري وصافي التبادل الحراري = صفر Thermometer and temperature scale اذا وجد جسمين معزولين وكلاهما في حالة اتزان حراري مع جسم ثالث يؤدي الى ان الجسمين في حالة اتزان حراري مع بعضهما البعض ويعرف بالقانون الصفري ويعتبر مهم لفكرة الثيرموميتر

3. Thermometer and temperature scale
Liquid change in length
Gas change p
Resistance
Thermocouple electric pot
Radiation
Magnetic

7. Fahrenheit scale Celsius scale
اعلى نقطة تحول الماء الى الغازية اوالصلبة ولكن اعتبر فهرنهايت درجة الانصهار هي درجة 32 بدلا من الصفر ودرجة الغليان للماء هي درجة 212 بدلا من 100 ML/NI=C-0/100-0=F-32/ c/100=F-32/180 F=9/5c+32 T(in c)= 32+9/5 T(in c)

8. Kelvin scale
T (in c)= T(in K)

9. Example
An object has atemp of 50 F what is its temp in degree celiuseies? Tc=5/9(Tf-32)=5/9(50-32)=10C T=Tc =283.15K

10. Expansion:
Any material, with some exceptional materials, whether it is a solid or liquid or gas, expands on heating and contracts on cooling. In general gases expand more than liquids and liquids expand more than solids for the same temperature rise. The amount solids expand is very small.

11. I- Expansion of solids:
Solids expand when heated in length, surface or area and volume. Usually the expansion occurs in all directions. Hollow solids expand as if they are rigid.
Linear Expansion of Solid:
Experiments show that the increase in length of a solid bar on heating depends on The original length of the bar, The increase in temperature, and Nature of material.
A metal rod fixed from one end and touching a lever pointer from the other end is heated using a flame. The pointer deflects to the right on heating and returns back on cooling the rod. This shows that the solid bar expands on heating and contracts on cooling. Solids expand by different amount. Brass for example expands more than iron and iron expands more than invar.

12. Thermal Expansion
∆L=αL∆ T
Coefficient of linear expension

14. Boyle s law
When gas is kept at const temp its pressure in inversely proportional to the volume
Pα1/v

15. Charles law
When the pressure of the gas is kept const volume directly proportional to the temp
vαt

16. Ideal gas equation
Pv=nRT R=8.31J/mole.K

18. An ideal gas occupies a volume of 100cm3 at 20c and a pressure of 100pa .determine the number of moles of gas in the container
PV =nRT

19. One mole of o gas is at pressure of 6 atm and atemp of 7c
One mole of o gas is at pressure of 6 atm and atemp of 7c . If the gas is heated at const vol until the pre triples what is the final temp? If the gas is heated

20. T=273+7=280 k
P2=3p1
P1/p/t1=3p1/t2
1/t1=3/t2 K

21. Heat capacity and spec
Heat capacity is defined as the amount of heat energy needed to raise the temp of a sample by 1 degree Celsius
السعة الحرارية انها مقدار الطاقة الحرارية اللازمة لرفع درجة حرارة كيلو جرام من المادة بمقدار درجة مئوية واحدة
Q=C∆T

22. Heat and Temperature.
Heat.
Heat is energy transferred from one body or system to another due to difference in temperature (Q)
Temperature.
Temperature is a quantitative description of hotness and coldness of body.

23. 4-Transmission of Heat:
Heat is transmitted from one place to another, from a higher to a lower temperature, in three different ways.
1-Conduction. 2- Convection. 3- Radiation

24. Heat conduction
Conduction is heat transfer by means of molecules agitation within a material without any motion of the material as a whole
Conduction is the transfer of heat within a substance molecule by molecule

26. When two objects are in physical contact H=Q/t=kA(∆ T/L) H rate of conduction heat transfer (W) K thermal conductivity (W/m.K) Q heat transferred A area t duration of heat transfer ∆T temperature difference between two ends

27. Heat convection
Convection is heat transfer by mass motion of a fluid such as air or water when the heated fluid is caused to move away from the source
of heat carrying energy with it

29. Heat Radiation
Energy is transferred by electromagnetic radiation .All of the earths energy is transferred from the sun by radiation

31. The relation ship governing radiation from hot objects is called the stefan Boltazmann law P=e A(T4-T4s) P is the net radiation power measured in W E is the emissivity (=1 for ideal radiator) A area T is the temp of the radiator in K T s is the temp of the surrounding in K σ=5.6x10-8 w/m2k4 is constant (stefan Boltazmann