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Question
A metal cube of length 4 cm radiates heat at the rate of 10 J/s. Find its emissive power at a given temperature.
Solution
Given: l = 4 cm, A = 6l2 = 6 × 16 cm2 = 96 × 10-4 m2
`Q/t = 10` J/s
To find: Emissive power (E)
Formula:
E = `Q/(At)`
Calculation:
From formula,
E = `10/(96 xx 10^-4)`
= 1041.66 J/m2s
The emissive power at a given temperature is 1041.66 J/m2s.
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