Domestic refrigerators

Water coolers

Room air conditioners

All of these

A. Domestic refrigerators

Convection

Radiation

Forced convection

Free convection

Parallel flow type

Counter flow type

Cross flow type

Regenerator type

Both the fluids at inlet (of heat exchanger where hot fluid enters) are in their coldest state

Both the fluids at inlet are in their hottest state

Both the fluids at exit are in their hottest state

One fluid is in hottest state and other in coldest state at inlet

The better insulation must be put inside

The better insulation must be put outside

One could place either insulation on either side

One should take into account the steam temperature before deciding as to which insulation is put where

Liquids

Energy

Temperature

Entropy

Reflected

Refracted

Transmitted

Absorbed

Grashoff number

Biot number

Stanton number

Prandtl number

One

Two

Three

Four

Free electrons

Atoms colliding frequency

Low density

Porous body

Stanton number

Biot number

Peclet number

Grashoff number

Wien's law

Planck's law

Stefan's law

Fourier's law

m²/hr

m²/hr °C

kcal/m² hr

kcal/m. hr °C

Directly proportional to the thermal conductivity

Inversely proportional to density of substance

Inversely proportional to specific heat

All of the above

0.1

0.23

0.42

0.51

Energy transferred by convection to that by conduction

Kinematic viscosity to thermal diffusivity

Inertia force to viscous force

None of the above

Absolute temperature (T)

I²

F

T

Watt/cm² °K

Watt/cm4 °K

Watt²/cm °K⁴

Watt/cm² °K⁴

W/m²K

W/m²

W/mK

W/m

Same

Less

Greater

None of these

Melting of ice

Boiler furnaces

Condensation of steam in condenser

None of these

Face area

Time

Thickness

Temperature difference

It is impossible to transfer heat from low temperature source to t high temperature source

Heat transfer by radiation requires no medium

All bodies above absolute zero emit radiation

Heat transfer in most of the cases takes place by combination of conduction, convection and radiation

Their atoms collide frequently

Their atoms are relatively far apart

They contain free electrons

They have high density

Absolute temperature

Square of temperature

Fourth power of absolute temperature

Fourth power of temperature

Q = [2πlk (T₁ - T₂)]/2.3 log (r₂/r₁)

Q = 2.3 log (r₂/r₁)/[2πlk (T₁ - T₂)]

Q = [2π (T₁ - T₂)]/2.3 lk log (r₂/r₁)

Q = = 2πlk/2.3 (T₁ - T₂) log (r₂/r₁)

Convection

Radiation

Conduction

Both convection and conduction

Cold body to hot body

Hot body to cold body

Smaller body to larger body

Larger body to smaller body

Parallel flow

Counter flow

Cross flow

All of these

Grey body

Brilliant white polished body

Red hot body

Black body

Conduction

Convection

Radiation

Conduction and radiation combined