Define Absorptive Power

The absorptive power of a body (or a surface) is defined as the ratio of the energy absorbed in a given time (or in a......

Define and Discuss on Angstrom Pyrheliometer

Pyrheliometer is an instrument used to measure the quantity of heat radiation and solar constant. Pyrheliometer designed by Angstrom is the simplest and most accurate.......

Explain Surface Temperature of the Sun

The Sun is a perfect black body of radius r and surface temperature T. According to Stefan’s law, the energy radiated by the Sun per......

What is Solar Constant?

The solar constant is the amount of radiant energy received per second per unit area by a perfect black body on the Earth with its......

Experimental Verification of Newton’s Law of Cooling

Let consider a spherical calorimeter of mass m whose outer surface is blackened. It is filled with hot water of mass m1. The calorimeter with......

What is Newton’s Law of Cooling

Newton’s law of cooling states that the rate of cooling of a body is directly proportional to the temperature difference between the body and the......

Stefan’s Law

Stefan’s law states that the total amount of heat energy radiated per second per unit area of a perfect black body is directly proportional to......

Wien’s Displacement Law

Wien’s displacement law states that the wavelength of the radiation corresponding to the maximum energy (λm) decreases as the temperature T of the body increases.......

Applications of Kirchoffs Law

Kirchhoff’s Laws are applications of two fundamental conservation laws: the Law of Conservation of Energy, and the Law of Conservation of Charge. (i) The silvered......

Explain Kirchoff’s Law

According to Kirchoff’s Law, the ratio of emissive power to the absorptive power corresponding to a particular wavelength and at a given temperature is always......

Explain Prevost’s theory of Heat Exchanges

Prevost applied the idea of thermal equilibrium to radiation. According to him the rate at which a body radiates or absorbs heat depends on the......

Explain Fery’s Black Body

Fery’s black body consists of a double walled hollow sphere having a small opening O on one side and a conical projection P just opposite......