chapter 8

Question 1

this is emitted from all objects that have a temperature greater than absolute zero

Answer 1

thermal infrared energy

Question 2

range of thermal infrared energy

Answer 2

3.0 - 14 um

Question 3

three types of energy transfer

Answer 3

conduction, convection, radiation

Question 4

conduction

Answer 4

transfer of energy from solid to solid

Question 5

convection

Answer 5

transfer of energy through liquid or gas

Question 6

radiation

Answer 6

transfer of energy through a vacuum

Question 7

___________discovered the infrared portion of the elect. mag. spectrum

Answer 7

Sir Frederick William Herschel

Question 8

modern infrared remote sensing detectors consist of these two substances:

Answer 8

mercury-doped germanium and indium antimonide

Question 9

reflective infrared range

Answer 9

.7 - 3 um

Question 10

thermal infrared range

Answer 10

3 -14 um

Question 11

kinetic heat

Answer 11

energy of particles of matter in random motion (all objects above absolute zero, -459.69 F, exhibit this motion

Question 12

calorie

Answer 12

amount of heat required to raise the temperature of 1g of water 1 degree C

Question 13

internal kenetic heal is _________ to ___________

Answer 13

converted to radiant energy

Question 14

radiant flux

Answer 14

electromagnetic energy exiting an object MEASURED in watts

Question 15

radiant temperature

Answer 15

the concentration of the amount of radiant flux exiting an object is its radiant temperature

Question 16

basis of thermal infrared remote sensing

Answer 16

there is a high positive correlation between the true kinetic temperature of an object and the amount of radiant flux radiated from the object. Therefore, we can utilize radiometers placed some distance from the object to measure its radiant temperature

Question 17

blackbody

Answer 17

theoretical construct that absorbs all the radiant energy striking it and radiates the maximum possible rate per unit area at each wavelength for any given temperature

Question 18

Stephan Boltzmann Law

Answer 18

total spectral radiant flux exitance of a blackbody is proportional to the fourth power of its absolute temperature

Question 19

emissivity

Answer 19

ratio between the radiant flux exiting a real-world selective radiating body and a blackbody at the same temp.

Question 20

all selectively radiating bodies have emissivities ranging from

Answer 20

0 < 1

Question 21

emissivity of distilled water from 8 - 14 um

Answer 21

.99

Question 22

graybody

Answer 22

emits proportionally to a blackbody (not dependent on wavelength)

Question 23

kirchoff’s radiation law

Answer 23

if reflectivity increases then emissivity must decrease. If emissivity increases then reflectivity must decrease