Download the app

Questions  

A solid copper sphere (density ρ and specific heat capacity c) of radius r at an initial temperature 200 K is suspended inside a chamber whose walls are at almost 0 K. The time required (in μs) for the temperature of the sphere to drop to 100 K is

Unlock the full solution & master the concept.

Get a detailed solution and exclusive access to our masterclass to ensure you never miss a concept
By Expert Faculty of Sri Chaitanya
a
727rρcσ
b
772rρcσ
c
277rρcσ
d
780rρcσ
NEW

Ready to Test Your Skills?

Check Your Performance Today with our Free Mock Tests used by Toppers!

detailed solution

Correct option is B

43πr3×ρCdTdt=σ4πr2T4⇒r3×ρCdTdt=σT4⇒rρC3σT4dT=dt⇒rρC3σ∫100200 dTT4=∫0t dt⇒rρC3σ∫100200 dTT4=∫0t dt⇒rρC9σ×1061−18=t∴t=7rρC72σ×106


ctaimg

Similar Questions

A solid copper cube of edges 1 cm is suspended in an evacuated enclosure. Its temperature is found to fall from 100oC to 99oc in 100 s. Another solid copper cube of edges 2 cm, with similar surface nature, is suspended in a similar manner. The time required for this cube to cool from 100oC to 99oC will be approximately

Get your all doubts cleared from
Sri Chaitanya experts

counselling
india
+91

phone iconwhats app icon