A spherical black body with a radius of 12 cm radiates 450 watt power at 500 K. If the radius were halved and the temperature doubled, the power radiated in watt would be.......?

A short-circulated coil is placed ina time varrying magnetic field. Electrical power is dissipated due to the current induced in the coil. If the number of turns were to be quadrupled and the wire radius halve,d the electrical power dissipated would be

A point charge causes an electric flux of -1.0 xx 10^3 Nm^2//C to pass through a spherical Gaussian surface of 10.0 cm radius centred on the charge - If the radius of the Gaussian surface were doubled, how much flux would pass through the surface?

An electric flux of -5xx10^3Nm^2C^-1 passes through a spherical gaussian surface of radius 20 cm due to the charge placed at its centre. If the radius of the gaussian surface is doubled, how much flux would pass through the surface?

According to Stefan's law of radiation, a black body radiates energy sigmaT^4 from its unit surface area every second where T is the surface temperature of the black body and sigma = 5.67 xx 10^-8 W//m^2 K^4 is known as Stefan's constant. A nuclear weapon may be thought of as a ball of radius 0.5 m. When detonated, it reaches temperature of 10^6 K and can be treated as a black body. Estimate the power it radiates

A small point object is placed in air at a distance of 60 cm from the convex spherical refracting surface of refractive index 1.5.If radius of curvatrure of the spherical surface is 25 cm,calculate the power of the refracting surface.

What is the excess pressure inside a bubble of soap solution of radius 5.00 mm,given that the surface tension of soap solution at the temperature (20^@C) is 2.50xx 10 2 N in 1 ? If an air bubble of the same dimension were formed at depth of 40.0 cm inside a container containing the soap solution (of relative density 1.20), what would be the pressure inside the bubble ? (1 atmospheric pressure is 1.01xx 105 Pa).