## Question

Each square meter of sun’s surface radiates energy at the rate of . Assuming that Stefan’s law applies to the radiation, the temperature of sun’s surface is (Stefan’s constant )

### Solution

From Stefan’s law

#### SIMILAR QUESTIONS

A one liter flask contains some mercury. It is found that at different temperatures the volume of air inside the flask remains the same. What is the volume of mercury in the flask? Given the coefficient of linear expansion of glass ^{o}C^{–1}, the coefficient of volume expansion of mercury is ^{o}C^{–1}.

A wire of cross-sectional area *A* at temperature *t* is held taut with negligible tension between two rigid supports. If the wire is cooled to a temperature what tension is developed in the wire? The coefficient of linear expansion is and the Young’s modulus of the wire is *Y*.

Two uniform brass rods *A* and *B *of length *l* and 2*l *and radii 2*r* and *r*respectively are heated to the same temperature. The ratio of the increase in the length of *A* to that of *B* is

Two rods of different materials having coefficients of thermal expansion and Young’s modulii *Y*_{1}, *Y*_{2} respectively are fixed between two rigid massive walls. The rods are heated such that they undergo the same increase in temperature. There is no bending of the rods. If the thermal stresses developed in the two rods are equal provided *Y*_{1} : *Y*_{2} is equal to:

The water equivalent of a copper calorimeter is 4.5 g. If the specific heat of copper is 0.09 cal.g^{–1o}C^{–1} the

A slab of stone of area 0.34 m^{2} and thickness 10 cm is exposed on the lower face to steam at 100^{o}C. A block of ice at 0^{o}C rests on the upper face of the slab. In one hour, 3.6 kg of ice is melted. Assume that the heat loss from the sides is negligible. The latent heat of fusion of ice is What is the thermal conductivity of the stone in units of Js^{–1}m^{–1o}C^{–1}?

An ice-box is made of wood 1.75 cm thick, lined inside with cork 2 cm thick. If the temperature of the inner surface of the cork is steady at 0^{o}C and that of the outer surface is steady at 12^{o}C, what is the temperature of the surface? The thermal conductivity of wood is 5 times that of cork.

The tungsten filament of an electric lamp has a surface area *A* and a power rating* P*. if the emissivity of the filament is is Stefan’s constant, the steady temperature of the filament will be

What are the dimensions of Stefan’s constant?

Experimental investigations show that the intensity of the solar radiation is maximum for a wavelength 4750 in the visible region. If the surface temperature of the sun is 6000 K, what is the value of the Wien’s constant*b*?