If temperature of a black body increases from $7°C$ to $287°\mathrm{C}$ , then the rate of energy radiation increases by

(a) ${\left(\frac{287}{7}\right)}^{4}$                  (b) 16
(c) 4                            (d) 2

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Stefan-Boltzmann law
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The area of a hole of heat furnace is . It radiates $1.58×{10}^{5}$ calories of heat per hour. If the emissivity of the furnace is 0.80, then its temperature is
(a) 1500 K            (b) 2000 K
(c) 2500 K            (d) 3000 K

Concept Questions :-

Stefan-Boltzmann law
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Two spheres P and Q, of same colour having radii 8 cm and 2 cm are maintained at temperatures 127$°\mathrm{C}$and 527$°\mathrm{C}$ respectively. The ratio of energy radiated by P and Q is
(a) 0.054             (b) 0.0034
(c) 1                   (d) 2

Concept Questions :-

Stefan-Boltzmann law
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

A body radiates energy 5W at a temperature of 127$°\mathrm{C}$. If the temperature is increased to 927$°\mathrm{C}$, then it radiates energy at the rate of
(a) 410 W                   (b) 81 W
(c) 405 W                   (d) 200 W

Concept Questions :-

Stefan-Boltzmann law
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The temperatures of two bodies A and B are respectively 727$°\mathrm{C}$ and 327$°\mathrm{C}$. The ratio of the rates of heat radiated by them is

(a)727:327                        (b) 5 : 3
(c) 25 : 9                           (d) 625 : 81

Concept Questions :-

Stefan-Boltzmann law
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Difficulty Level:

The energy emitted per second by a black body at 27$°\mathrm{C}$ is 10 J. If the temperature of the black body is increased to 327$°\mathrm{C}$, the energy emitted per second will be

(a) 20 J              (b) 40 J
(c) 80 J              (d) 160 J

Concept Questions :-

Stefan-Boltzmann law
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The radiant energy from the sun incident normally at the surface of earth is . What would have been the radiant energy incident normally on the earth, if the sun had a temperature twice of the present one ?

(a)                     (b)
(c)                     (d)

Concept Questions :-

Stefan-Boltzmann law
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

If the temperature of the sun (black body) is doubled, the rate of energy received on earth will be increased by a factor of
(a) 2                         (b) 4
(c) 8                         (d) 16

Concept Questions :-

Stefan-Boltzmann law
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The ratio of energy of emitted radiation of a black body at 27$°\mathrm{C}$ and 927$°\mathrm{C}$ is
(a) 1 : 4                  (b) 1 : 16
(c) 1 : 64                 (d) 1 : 256

Concept Questions :-

Stefan-Boltzmann law
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Two spherical black bodies of radii ${\mathrm{r}}_{1}$ and ${\mathrm{r}}_{2}$ and with surface temperature ${\mathrm{T}}_{1}$ and ${\mathrm{T}}_{2}$ respectively radiate the same power. Then the ratio of ${\mathrm{r}}_{1}$ and ${\mathrm{r}}_{2}$ will be

(a) ${\left(\frac{{\mathrm{T}}_{2}}{{\mathrm{T}}_{1}}\right)}^{2}$                (b) ${\left(\frac{{\mathrm{T}}_{2}}{{\mathrm{T}}_{1}}\right)}^{4}$
(c) ${\left(\frac{{\mathrm{T}}_{1}}{{\mathrm{T}}_{2}}\right)}^{2}$                (d) ${\left(\frac{{\mathrm{T}}_{1}}{{\mathrm{T}}_{2}}\right)}^{4}$

Concept Questions :-

Stefan-Boltzmann law