Assertion : The equivalent thermal conductivity of two plates of same thickness in contact is less than the smaller value of thermal conductivity.
Reason : For two plates of equal thickness in contact the equivalent thermal conductivity is given by : $\frac{1}{K} = \frac{1}{{{K_1}}} + \frac{1}{{{K_2}}}$

  • [AIIMS 1997]
  • A

    If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

  • B

    If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

  • C

    If the Assertion is correct but Reason is incorrect.

  • D

    If both the Assertion and Reason are incorrect.

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