Question

A thin square steel plate with each side equal to 10 cm is heated by a blacksmith. The rate of radiated energy by the heated plate is 1134 watts. The temperature of the hot steel plate is ______.

(Stefan's constant σ = 5.67 × 10^-8 watt m^-2K^-4 emissivity of the plate = 1)

Options

• 570 K

• 1189 K

• 2500 K

• 750 K

Answer 1

A thin square steel plate with each side equal to 10 cm is heated by a blacksmith. The rate of radiated energy by the heated plate is 1134 watts. The temperature of the hot steel plate is 1189 K.

Explanation:

`sigmaeAT^4 = 1134`

⇒ T = `(1134/(sigmaeA))^{1/4} = [1134/(5.67 xx 10^8 xx 1 xx (1)^2)]^{1/4}`

T = 1189 K