# Fundamental Physics/Heat

(Redirected from Heat)

## Heat

Heat comes from heat sources such as Fire, Light, Wind , Friction by rubbing of 2 objects against each other . Temperature is the characteristic of Heat . An indication of heat intensity . High temperature indicates hot sensation . Low temperature indicates cold sensation . Temperture is denoted as T measured in degree o

Standard Temperatures

 Standard Temperatures Degree C Degree F Degree K Frozen temperature 0 oC Boiling temperature 100oC Room temperature 25oC

There are 3 Temperature measurement systems namely

conversion between these systems of temperature can be done as shown below

 Convert from to Formulas Fahrenheit Celsius °C = (°F – 32) / 1.8 Celsius Fahrenheit °F = °C × 1.8 + 32 Fahrenheit kelvin K = (°F – 32) / 1.8 + 273.15 kelvin Fahrenheit °F = (K – 273.15) × 1.8 + 32

Observations indicate that

• Dark and thin matter is easy to absorb heat energy than light and thick matter
Dark and thin clothes dry faster than bright and thick clothes
• Heat travels from high temperature to low temperature
Heat always travel from hot water to cold water
• Heat transfer through 3 states of matter Solid, Liquid and Gas through 3 phases Heat conduction, Heat convection and Heat radiation

## Heat Absorbtion laws

### First Law

Heat flows from high temperature to low temperature

${\displaystyle T_{2}>T_{1}}$ heat transferes from T2 to T1
${\displaystyle T_{2} heat transferes from T1 to T2
${\displaystyle T_{2}=T_{1}}$ no heat transfer

### Second Law

Heat interact with matter to create change in matter's temperature


If temperature of matter is at To . Matter's temperature change to T1 when matter interacts with heat . Then, change inn matter's temperature

${\displaystyle \Delta T=T_{2}-T_{1}}$

### Third Law

Heat energy absorb by matter is directly proportional with matter's mass, change in matter's temperature and matter's capability to absord heat

${\displaystyle Q=mc\Delta T=mc\Delta T=mc(T_{2}-T_{1})}$

### IV Law

Heat transfer between 2 objects of different mass

Heat energy absorb by mass 1

${\displaystyle Q_{1}=m_{1}cT_{1}}$

Heat energy absorb by mass 2

${\displaystyle Q_{2}=m_{2}cT_{2}}$

${\displaystyle T_{1}>T_{2}}$

${\displaystyle Q_{1}-Q_{2}=m_{1}cT_{1}-m_{2}cT_{2}=(m_{1}-m_{2})c(T_{1}-T_{2})}$

${\displaystyle T_{2}>T_{1}}$

${\displaystyle Q_{2}-Q_{1}=m_{2}cT_{2}-m_{1}cT_{1}=(m_{2}-m_{1})c(T_{2}-T_{1})}$

## Heat transfer

Heat transfer through matter in 3 phases namely Heat conduction, Heat convection and Heat radiation

• Heat conduction . Matter change its temperature when it is in contact with heat energy
${\displaystyle \Delta T=T_{2}-T_{1}}$
${\displaystyle E=mc\Delta T=mc(T_{2}-T_{1})}$
• Heat convection . Matter absorbs heat energy to its maximum level and gives off visible light
${\displaystyle E=hf_{o}}$
${\displaystyle f_{o}={\frac {C}{\lambda _{o}}}}$
• Heat radiation . Matter absorbs heat energy to its maximum level and gives off free electron
${\displaystyle E=E_{o}+E_{e}=hf_{o}+{\frac {1}{2}}mv^{2}}$
${\displaystyle v={\sqrt {{\frac {2}{m}}(E-hf_{o})}}}$
${\displaystyle v>0}$ when ${\displaystyle E-hf_{o}>0}$
${\displaystyle {\frac {E}{h}}>f_{o}}$

## Electromagnetic heat

Experiment has shown that conductor interacts with electricity can create Electromagnetic heat energy

### Straight line conductor

${\displaystyle B=Li={\frac {\mu i}{2\pi r}}}$
${\displaystyle R(T)=R_{o}+nT}$ for electric conductor
${\displaystyle R(T)=R_{o}e^{nT}}$ for electric conductor
${\displaystyle E_{R}=I^{2}R(T)=mC\Delta T}$
${\displaystyle m={\frac {I^{2}R(T)}{C\Delta T}}}$
${\displaystyle C={\frac {I^{2}R(T)}{m\Delta T}}}$

### Coil of N circular loops

Coil of N circular loops without any magnetic material object placed inside the coil's turns

${\displaystyle B=Li=\mu _{o}i{\frac {N}{l}}}$
${\displaystyle f_{o}={\frac {C}{\lambda _{o}}}}$
${\displaystyle E=hf_{o}}$
${\displaystyle h=p\lambda _{o}}$
${\displaystyle C=\lambda _{o}f_{o}}$

Coil of N circular loops with a magnetic material object placed inside the coil's turns

${\displaystyle B=Li=\mu i{\frac {N}{l}}}$
${\displaystyle f={\frac {C}{\lambda }}}$
${\displaystyle E=hf}$
${\displaystyle h=p\lambda }$
${\displaystyle C=\lambda f}$

## Applications

Natural phenomenon occurs in nature like

Electronics component that converts heat energy to electrical energy

1. Thermistor

Electric machines that converts heat energy to electrical energy