A metal cube of each side 0.05 m long emits 0.6k cal in 80 seconds, Calculate the emissive power of its surface.

A metal cube of each side 2 cm long emits 0.16 kcal of heat in 100s. Calculate the emissive power of the cube in joule at that temperature. J = 4200 J//kcal .

A metal cube has each side 2.5 cm long and radiates 0.36 kcal//min . What is the emissive power of its surface? If the emissivity of its surface is 0.4, what would be the emissive power of the cube if it were perfectly black?

A body of surface are 15xx10^(-3)m^2 emits 0.3 kcal in 40 second at a temperature 70^(@)C . The emissive power of the surface at that temperature is

A metal cube has each side of length 1 m losses all its energy at a rate of 3000 watt. If the emissity is 0.4, Find its temperature (Given:a= 5.767xx10^-8J//m^2sk^-1 )

A wire of mass 0.5 gram and length of 0.5 m is under a tension of 2 kg wt. Calculate the frequency of its fundamental mode. (g = 9.8 m/s^2)

A current of 0.2 A passes through a metal wire for 20 seconds. Calculate the number of electrons passing through the cross section of the wire during this time. (The charge on an electron = 1.6 times 10^(-19) C)

One hundred twenty five small liquid drops, each carrying a charge of 0.5muC and each of diameter 0.1m form a bigger drop. Calculate the potential at the surface of the bigger drop.

A filament of an evacuated light blue has length 10 cm, diameter 0.2mm and emissivity 0.2. Calculate the power it radiates at 2000 K ( sigma=5.67xx10^-8 J/m^2k^4 )

A metal cube of side 1 m is subjected to a force. The force acts normally on the whole surface of a cube and its volume changes by 1.5 xx 10^-5 m^3 . The bulk modulus of the metal is 6.6 xx 10^10 N//m^2 . Calculate change in pressure.