A 100 W electric bulb was switched on in a 2.5 m × 3 m

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A 100 W electric bulb was switched on in a 2.5 m × 3 m × 3 m size thermally insulated room having a temperature of 20°C. The room temperature at the end of 24 hours will be

1. 321 °C
2. 341 °C
3. 450°C
4. 470°C

Correct Option: D

Heat generated by bulb = 100 × 24 × 60 × 60 Joule.
∴ Heat dissipated = ρ × V × C_v × (T – 20)
⇒ 100 × 24 × 60 × 60 = 1.24 × 9 × 2.5 × 3 × C_v (T – 20)
⇒ T = 450º