Two balls of same material and finish have their diameters in the ratio of 2: 1 and both are heated to same temperature and allowed to cool by radiation. Rate of cooling by big ball as compared to smaller one will be in the ratio of

Heat and Mass Transfer
Two balls of same material and finish have their diameters in the ratio of 2: 1 and both are heated to same temperature and allowed to cool by radiation. Rate of cooling by big ball as compared to smaller one will be in the ratio of

0.16736111111111

0.043055555555556

0.042361111111111

0.084027777777778

0.16736111111111

0.043055555555556

0.042361111111111

0.084027777777778

ANSWER DOWNLOAD EXAMIANS APP

Heat and Mass Transfer
A composite slab has two layers of different materials with thermal conductivities k₁ and k₂. If each layer has the same thickness, then the equivalent thermal conductivity of the slab will be

k₁ k₂

(k₁ + k₂)/ k₁ k₂

(k₁ + k₂)

2 k₁ k₂/ (k₁ + k₂)

k₁ k₂

(k₁ + k₂)/ k₁ k₂

(k₁ + k₂)

2 k₁ k₂/ (k₁ + k₂)

ANSWER DOWNLOAD EXAMIANS APP

Heat and Mass Transfer
Kirchhoff's law states that

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

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

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

ANSWER DOWNLOAD EXAMIANS APP

Heat and Mass Transfer
The total radiation from a black body per second per unit area is ________ fourth power of the absolute temperature. This statement is known as Stefan Boltzmann law.

Inversely proportional to

Equal to

Directly proportional to

None of these

Inversely proportional to

Equal to

Directly proportional to

None of these

ANSWER DOWNLOAD EXAMIANS APP

Heat and Mass Transfer
Pick up the wrong case. Heat flowing from one side to other depends directly on

Time

Temperature difference

Thickness

Face area

Time

Temperature difference

Thickness

Face area

ANSWER DOWNLOAD EXAMIANS APP

Heat and Mass Transfer
When heat is transferred from one particle of hot body to another by actual motion of the heated particles, it is referred to as heat transfer by

Convection

Conduction and convection

Conduction

Radiation

Convection

Conduction and convection

Conduction

Radiation

ANSWER DOWNLOAD EXAMIANS APP

Heat and Mass Transfer

Heat and Mass Transfer Two balls of same material and finish have their diameters in the ratio of 2: 1 and both are heated to same temperature and allowed to cool by radiation. Rate of cooling by big ball as compared to smaller one will be in the ratio of

Heat and Mass Transfer A composite slab has two layers of different materials with thermal conductivities k₁ and k₂. If each layer has the same thickness, then the equivalent thermal conductivity of the slab will be

Heat and Mass Transfer Kirchhoff's law states that

Heat and Mass Transfer The total radiation from a black body per second per unit area is ________ fourth power of the absolute temperature. This statement is known as Stefan Boltzmann law.

Heat and Mass Transfer Pick up the wrong case. Heat flowing from one side to other depends directly on

Heat and Mass Transfer When heat is transferred from one particle of hot body to another by actual motion of the heated particles, it is referred to as heat transfer by

Heat and Mass Transfer
Two balls of same material and finish have their diameters in the ratio of 2: 1 and both are heated to same temperature and allowed to cool by radiation. Rate of cooling by big ball as compared to smaller one will be in the ratio of

Heat and Mass Transfer
A composite slab has two layers of different materials with thermal conductivities k₁ and k₂. If each layer has the same thickness, then the equivalent thermal conductivity of the slab will be

Heat and Mass Transfer
Kirchhoff's law states that

Heat and Mass Transfer
The total radiation from a black body per second per unit area is ________ fourth power of the absolute temperature. This statement is known as Stefan Boltzmann law.

Heat and Mass Transfer
Pick up the wrong case. Heat flowing from one side to other depends directly on

Heat and Mass Transfer
When heat is transferred from one particle of hot body to another by actual motion of the heated particles, it is referred to as heat transfer by