NEET
- Exam
- NEET
- Subject
- Physics
- Chapter
- Thermal Properties of Matter
NEET · Physics · Thermal Properties of Matter
Assertion : A body that is a good radiator is also a good absorber...
Assertion : A body that is a good radiator is also a good absorber of radiation at a given wavelength.
Reason : According to Wrichoff a law the absorptivity of a body is equal to its emissivity at a given wavelength.
Options
- ABoth (A) and (R) are true and (R) is the correct explanation of (A).
- BBoth (A) and (R) are true and (R) is NOT the correct explanation of ((\mathrm{A})).
- C(A) is true but (R) is false.
- DBoth (A) and (R) are false.
Correct answer
A. Both (A) and (R) are true and (R) is the correct explanation of (A).
Step-by-step solution
A good radiator, which emits energy efficiently, will also absorb energy efficiently at the same wavelength.
Therefore assertion is true.
The reason provided references Kirchhoff's law of thermal radiation, which states that for a body in thermal equilibrium, the absorptivity (the ability to absorb radiation) is equal to its emissivity (the ability to emit radiation) at a specific wavelength. This law applies to all materials and is fundamental in thermodynamics and radiative transfer.
Reason is the correct explanation of assertion