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Flashcards in Basics Deck (12):
1

Three modes of heat transfer

Conduction
Convection
Radiation

2

What is conduction

Heat flow only because of temperature gradient

No observable motion of matter

3

Metals flow of heat

Motion of free electrons

4

Convection

Observed by the movement of the fluid

5

Thermal conductivity vs heat transfer coefficient

Instrinsic property of substance vs combination of many things

6

Natural convection

Buoyancy forces created by density differences and density differences are caused by temperature gradient

7

Radiation

Transfer of energy through space in the form of electromagnetic waves

Radiation becomes important at high temperature and unaffected by flow

Conduction convection not affected by temperature it by flow mostly

8

Radiation

Radiation itself is not an energy or heat.

Heat is released when electromagnetic radiations which are pockets of photons carried by the waves strike an object

An ideal black body will absorb all the radiation which strikes it.

9

EM waves

They do not need to medium to propagate

However when they strike a object, they are transmitted reflected or absorbed

10

How are EM waves produced?

An oscillating charged particle will create an oscillation electric and magnetic wave

11

Radiation

May be by electric bombardment electric discharge and so on

12

Radiation

All materials above absolute zero emit radiation