Rankers Physics

Uncategorized: Practice Problem & Solution

A black body at $227^{\circ}\text{C}$ radiates heat at the rate of $7 \text{ cal}/\text{cm}^2 \text{ s}$. At a temperature of $727^{\circ}\text{C}$, the rate of heat radiated in the same units will be (2009)
50
112
80
60

Solution Explained:

To solve this problem, we apply the core principles of Uncategorized. Understanding the underlying formula is key to arriving at the correct answer below:

$E \propto T^4 \Rightarrow \frac{E_2}{E_1} = (\frac{T_2}{T_1})^4 = (\frac{727+273}{227+273})^4 = (\frac{1000}{500})^4 = 16$. So, $E_2 = 16 \times 7 = 112 \text{ cal}/\text{cm}^2 \text{ s}$.

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