Question

All bodies at a temperature above absolute zero emit thermal radiation. a)-True b)-False

Answer 1

Answer:

a). TRUE

Explanation:

Absolute zero temperature is the lowest possible temperature that can be achieved where no heat energy remains in the body. Absolute zero temperature is 0 k in the Kelvin scale and -273.16 degree Celsius in Centigrade scale.

             All bodies with temperature greater than absolute zero emits energy in the form of electro magnetic radiation. Two laws namely Stefan Boltzmann law and Wein's law gives the basis of the fact that bodies with temperature greater than absolute zero temperature emits electromagnetic radiation.

Stefan Boltzmann law : It states the relationship between temperature of the body and radiations that it can emit.

                         E = σ. $T^{4}$

where E = radiation emissions

           σ =  Stefans Boltzmann constant

           t is temperature

Wein's Law : It states the temperature of the object and the wavelength at which the body emits maximum radiations.

$\lambda _{max} = \frac{b}{T}$

where λ is wavelength

           b  is a constant

           T is temperature