Start Free Mock LoginAlready registered? Login here

Physics - Heat & Thermo Question with Solution | TestHub

PhysicsHeat & ThermoHeat TransferMedium2 min

PhysicsMediumnumerical

A black aluminium sphere of radius 4 cm ( $ρ = 2700$ kg m⁻³, $c = 900$ J kg⁻¹ K⁻¹) cools in a chamber with walls near 0 K, from 800 K to 400 K. Find the time, in hours.

Answer:

0.70

Solution:

$t = \frac{r ρ c}{9 σ} (\frac{1}{T _{2}^{3}} - \frac{1}{T _{1}^{3}}) = \frac{0.04 \times 2700 \times 900}{9 \times 5.67 \times 1 0 ^{- 8}} (\frac{1}{40 0 ^{3}} - \frac{1}{80 0 ^{3}}) = 2.604 \times 1 0^{3}$ s = $0.7$ h.

Subject:PhysicsTopic:Heat & ThermoSubtopic:Heat Transfer

⏱ 2m

Doubts & Discussion

Loading discussions...