Question

A star has a surface area of 6.29x1018 m2. How much power does it radiate if it has a surface temperature of 7005 K? Submit your answer in exponential form.

Answer 1

we are asked to determine the power irradiated by a star given its area and temperature.

To do that we will use the following formula:

`P=\sigma AT^4`

Where:

`\begin{gathered} P=power \\ A=\text{ area} \\ T=\text{ temperature} \\ \sigma=\text{ constant} \end{gathered}`

The constant sigma is equivalent to:

`\sigma=5.7*10^(-8)Wm^(-2)K^(-4)`

Now, we substitute the values:

`P=(5.7*10^(-8)Wm^(-2)K^(-4))(6.29*10^(18)m^2)(7005K)^4`

Solving the operations:

`P=8.63*10^(16)W`

And thus we get the power of the start.