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NEET2008PhysicsThermal Properties of MatterActual

A slab consists of two layers of different materials of the same thickness and having thermal conductivities (K₁ ) and (K₂ ) are connected in series. The equivalent thermal conductivity of the slab is

Options

  1. A( 2 K₁ K₂ K₁+K₂ )
  2. B( K₁ K₂ )
  3. C( K₁ K₂ K₁+K₂ )
  4. D(K₁+K₂ ).

Correct answer

A. ( 2 K₁ K₂ K₁+K₂ )

Step-by-step solution

aligned & (a) : In series combination, t K₁ + t K₂ = 2 t K & 1 K₁ + 1 K₂ = 2 K K= 2 K₁ K₂ K₁+K₂ . aligned

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