HEAT TRANSFER MODES

Question 1

the three modes of heat transfer

Answer 1

• conduction
• convection
• radiation

Question 2

is the heat transfer in bodies that ar ein contact with each other. the transfer is due to the temperature difference of the bodies in contact

Answer 2

conduction

Question 3

it is due to the collision of molecules of the bodies in contact

Answer 3

conduction

Question 4

it is the heat transfer due to the motion of the fluids. There are natural and forced convection modes of heat transfer

Answer 4

convection

Question 5

in this type of convection the fluid motion arises from the changes in the density of the fluid due to thermal expansion. Cold fluids tend to go down and puh the warm fluids up, then the warm fluids become cold and the cold fuids become warm repeating the cycle

Answer 5

Natural Convection

Question 6

this type of convection is when a force is applied to the fluid to promote displacement of the fluid together with heat

Answer 6

Forced Convection

Question 7

2 types of Convection

Answer 7

natural convection
forced convection

Question 8

this is the mechanism of heat transfer is by excitation of atoms. This heat transfer doe snot need direct contact

Answer 8

Radiation

Question 9

it is the measure of how well an object radiates. This value is higher dor darker/black objects.

Answer 9

emissivity

Question 10

the object with the highest emissivity is an ideal object called

Answer 10

blackbody with an emissivity of 1

Question 11

it is the response of most materials to heat. It also expands when heated and contracts when cooled

Answer 11

Thermal Expansion

Question 12

two types of thermal expansion

Answer 12

Linear expansion
Volumetric expansion

Question 13

what thermal expansion has this formula?

ΔL = αLΔT

Answer 13

Linear Expansion

Question 14

what thermal expansion is this?
ΔV = Vo β ΔT

Answer 14

volumetric expansion