CONVECTION AND CONDUCTION

Question 1

There is no actual movement of molecules in receiving from surface of heat, molecules vibrates and pass on energy to adjacent molecule

Answer 1

Conduction

Question 2

It is a physical process involving the transfer of heat from hot area to cold area

Answer 2

Heat Transfer

Question 3

3 basic mechanisms of Heat Transfer

Answer 3

Conductio, Convection, Radiation

Question 4

Difference of temperature between two end

Answer 4

Driving force

Question 5

There is a actual physical movement of molecules

Answer 5

Convection

Question 6

Volume of K mainly depends upon:

Answer 6

Temperature, Nature of Material

Question 7

It is the quantity of heat that flows across a unit surface area in unit time, when the temperature drop is unity

Answer 7

Thermal Conductivity

Question 8

Two types of resistance

Answer 8

Resistance in series
Resistance in Parallel

Question 9

Thermal Conductivities of liquid

Answer 9

0.62

Question 10

Thermal Conductivity of Copper

Answer 10

379

Question 11

Thermal conductivity of gases

Answer 11

0.03

Question 12

What are the methods need to take average area

Answer 12

Arithmitic Mean
Log Mean Value

Question 13

If the tempearture is not constant, what are the 2 methods need to be use

Answer 13

Aritmitic Temperature
LMTD

Question 14

It takes place in solid and fluids whose movement is restricted

Answer 14

Conduction

Question 15

Longer distance

Answer 15

Radiation

Question 16

There is no actual contact in source of the heat

Answer 16

Convection

Question 17

The motion of the fluid results from the density changes in heat transfer

Answer 17

free or natural convection

Question 18

the fluid is forced to flow by pressure differences

Answer 18

forced convection

Question 19

what flow when the reynolds number is above 6000

Answer 19

Turbulent Flow

Question 20

Nre below 2100

Answer 20

Laminar flow

Question 21

What type of resistance when the total amount of heat transfer is equal to the sum of heat transfer by all the individual resistance in the same time of period

Answer 21

Parallel

Question 22

individual fluid has a great effect on the heat-transfer coefficient h, often called

Answer 22

film coefficient

Question 23

the motion of the fluid results from the density changes in heat transfer

Answer 23

Free or Natural Convection

Question 24

NRe between 2100 and 6000

Answer 24

Transitional region

Question 25

Formula of rate?

Answer 25

rate= driving force/resistance

Question 26

The most important convective heat-transfer process industrially is

Answer 26

cooling or heating a fluid flowing inside a closed circular conduit or pipe

Question 27

it takes place in solid and fluids whose movement is restricted

Answer 27

Conduction

Question 28

bodies that reject heat trasnfer

Answer 28

refracted

Question 29

it is the most important of all heat transfer

Answer 29

radiation

Question 30

heat can floe only when there is a temperature difference

Answer 30

conduction - fourier’s law