Heat Flashcards
Heat
Denoted by q
Heat is a form of energy which always flows from hot body to cold body
Si joule
Cgs unit calorie
100 gm ki manaki intha calories vastai antaru,
1 calorie =4.186 jouls
4.2 jouls
1 k cal 42000 jouls.
British thermal undit 252 calories
Heat is different from temperature
Temperature
The degree of hotness or cold ness of that body,
Degree, faren heit kelvin
The relationship between different scales of a temp.
C/100= f-32/180 = k-273/100
At which scale both Fahrenheit and celsius scale readings are same
At -40 °c
Kelvin, celsius fahrenheit
Celsius 0 to 100 no of divisions 100
Fahrenheit 32 to 212 nonof divisions 180
Kelvin 273 to 373 no of divisions 100
Freezing point of the water
0 c , 32 f , 273 k
Boiling point of the water 100 °c
Thermometer
Discovered by gelilio, air used by first time
Working principle of the thermometer is every substance expands on heating,
Types of thermometer
Clinical , only for measuring temp of human body, 35 to 42 95f to 110f
Normal temperature of human 36.9 / 37
98.4 f 310 k
Why mercury used in thermometer
Mercury has low specific heat,
0.033 cal / g. °c
Gud conductor of heat
Uniform expansion
Water has high specific heat.
Bad conductor of heat
Non uniform expansion
Cold countries lo alcohol untadi, mercury undadu, the frezing point of mercury is -39° c
Freezing point of alcohol -115 ° c
Specific heat
The amount of heat required to rise temp of body by one degree centigrade
Q/ m dt
M mass
Dt temp change
Cgs unit calorie/ kg °c
Pb 0.030
Hg 0.033
Fast ga heat avuthundi ante specific heat takkuva undi ani
Lead ekuvaga kalapadam valla maggie anedi fast ga udukuddii takkuva specific heat unte fast ga heat avuddi
Water is used as coolant why
Which one heat boils fast water or oil, sand
Specific heat which one has low it heat fast, samosa bayataki challa lopalaa heat , samosa use chesevatiki specific ekuva untadi anduke adi pogottukovadaniki time pattiddi
Sand has low oil has low then water
Six maximum minimum
To measure the maximum and
minimum temperature in particular day called six max and min
Optical pyro meter
To measure high temperature
To study high temperature caled pyrometer
Crayo meter.
To measure the low temperatures
Calorie meter to measure the specific heat of the water
Bomb caloriemeter
Calorific values of food components and fules
Expansion of the solids,
Linear if solid is heated only length expanded
Superexpanded l and b
Cuboidal l and b and h
Alpha beta gamma 1 :2:3
Why current wires are in loose
Winter lo contract avythai andukani loose ga vadulutharu
Gases to liquid called condensation
Gas to liquid
oka gas hydrogen liquid ga maralante enthentha temperature ivalo
Liquid hydrogen -252 . 8 c
Liquid oxygen -183°c.
Arogn -182 ivali
Liquid N2 -196°c
Liquid nitrogen is used to store the animal sperm
Sublimation
Camphor
Kalara undalu.
Nh4cl ammonium chloride
Solid co2 dry ice
Transmissions of heat
Conduction of heat
Without actual movement of particles
Medium required
Convection
Medium required
Radiation
Speed more
Thermo flask
Dewar, vaccum flask
Agbr
Inner later and outer layer ki vaccum untadi annamata, heat transfer avvalante 3 methods untai,
Lopala posina vedi tea bayataii povadaniki medium kavali so andukani medium tesestaru coating poostaru,,
