A metal ball of surface area 100 c m 2 at 42 7 ∘ C is in a vessel at 2 7 ∘ C. The emissivity is 0.5. Find the net rate of loss of heat in watts (one decimal; σ = 5.67 × 1 0 − 8 ).

P = ε σ A ( T 4 − T 0 4 ) = 0.5 × 5.67 × 1 0 − 8 × 0.01 × ( 70 0 4 − 30 0 4 ) = 65.8 W.

Start Free Mock LoginAlready registered? Login here

Physics - Heat & Thermo Question with Solution | TestHub

PhysicsHeat & ThermoHeat TransferMedium2 min

PhysicsMediumnumerical

A metal ball of surface area 100 $c m^{2}$ at $42 7^{\circ}$ C is in a vessel at $2 7^{\circ}$ C. The emissivity is 0.5. Find the net rate of loss of heat in watts (one decimal; $σ = 5.67 \times 1 0^{- 8}$ ).

Answer:

65.80

Solution:

$P = ε σ A (T^{4} - T_{0}^{4}) = 0.5 \times 5.67 \times 1 0^{- 8} \times 0.01 \times (70 0^{4} - 30 0^{4}) = 65.8$ W.

Subject:PhysicsTopic:Heat & ThermoSubtopic:Heat Transfer

⏱ 2m

Doubts & Discussion

Loading discussions...