HEAT AND MASS TRANSFER QUIZ

Decreases

Increases

May increase or decrease depending on temperature

Remain constant

kcal/m²

kcal/m² hr °C

kcal/hr °C

kcal/m hr °C

Their atoms collide frequently

They have high density

Their atoms are relatively far apart

They contain free electrons

A complete separation between hot and cold fluids

Direct mixing of hot and cold fluids

Flow of hot and cold fluids alternately over a surface

Generation of heat again and again

U.Cmin

Cmin/U

U/A.Cmin

U/Cmin

Water

Melting ice

Solid ice

Steam

K cal m/hr m² °C

K cal/hr m² °C

K cal/kg m² °C

K calm/hr °C

0.7

0.3

0.1

1.7

None of these

Radiation

Convection

Conduction

The ratio of the emissive power and absorptive power of all bodies is the same and is equal to the emissive power of a perfectly black body

None of these

The total radiation from a black body per second per unit area is directly proportional to the fourth power of the absolute temperature

The wave length corresponding to the maximum energy is proportional to the absolute temperature