Heat and Thermal ExpansionHard
Question
The emissive of a black body at T = 200 K is 100 Watt/m2. Consider a body B of area A = 10m2, coefficient of reflectivity r = 0.3 and coefficient of transmission t = 0.5 its temperature is 300 K. Then which of the following is incorrect :-
Options
A.The emissive power of B is 20 W/m2
B.The emissive power of B is 200 W/m2
C.The power emitted by B is 200 Watt
D.The emissivity of B is = 0.2
Solution
Ans(A)
For body A
P = σAT4
= 100 = σ × 3004
For body B
= (σT4) ∈ = (1 - 0.5 - 0.3) × [σ × 3004]
= 0.2 × 100 = 20W/m2
For body A
P = σAT4
= 100 = σ × 3004For body B
= (σT4) ∈ = (1 - 0.5 - 0.3) × [σ × 3004]= 0.2 × 100 = 20W/m2
Create a free account to view solution
View Solution FreeMore Heat and Thermal Expansion Questions
540 g of ice at 0oC is mixed with 540g of water at 80oC. The temperature of the mixture is (Give latent heat of fusion o...Two plates of equal areas are in contact with each other. Their thickness are 2 cm ans 3cm respectively. Temperature of ...n moles of an ideal triatomic linear gas undergoes a proses in which the temperature changes with volume as T = k1V2 whe...When water is heated from 0oC to 4oC and CP and CV are specific heats at constant pressure and constant volume respectiv...The figure shows two thin rods, one made of aluminum [α = 23 × 10-6 (Co)-1] and the other of steel [α = 1...