Let thermal conductivity of M1 be K′.
Using heat current relation for steady state conduction,
16K′A(100−80)=8KA(80−0)
⇒16K′×20=8K×80⇒K′=8K
Two metallic blocks M_1 and M_2 of same area of cross-section are connected to each other (as shown in figure). If the thermal conductivity of M_2 is…
JEE Main 2022 — Physics Thermodynamics
2022mcqeasy
Two metallic blocks M1 and M2 of same area of cross-section are connected to each other (as shown in figure). If the thermal conductivity of M2 is K then the thermal conductivity of M1 will be : [Assume steady state heat conduction]
Official previous-year question
Held on 24 Jun 2022 · Verified 6 Jul 2026.
Options
- A
10K
- B
8K
- C
12.5K
- D
2K
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