Question

Assertion (A) Radiation is the fatest mode of transmissin of heat
Reason (R ) : Conduction and convection require a medium for transmission of heat where as heat radiations can travel through vaccum .
A. both a and r are correct and r is the correct explanation of a
B. both a and r are correct but ra is not the correct explanation of a
C. a is correct and r is incorrect
D. both a and r are incorrect

Answer 1

Correct Answer - b
Radiation is the fastest mode of transmission of heat It does not require any medium as , it transmits heat in the form of electromageneitic waves .But conduction and convenction required a material medium for transmission of heat so A and R are correct but R is not the correct explanation of A