Question

What maximum power can be radiated by a 10-cm-diameter solid lead sphere? Assume an emissivity of 1.

Solution

Verified
Answered 2 months ago
Answered 2 months ago
Step 1
1 of 2

The power P:=dQdtP:=\frac{dQ}{dt} that is radiated from an object with surface AA, that has emissivity ee, at temperature TT, is given by

P=eσAT4,P=e\sigma AT^4,

where σ\sigma=5.67108 Wm2K4\cdot 10^{-8}~\mathrm{\frac{W}{m^2K^4}} is the Stefan-Boltzmann constant\textit{Stefan-Boltzmann constant}.

At first it might seem there is a problem, since we're not given a definite temperature: that'd mean the answer is infinity, since we can increase the temperature to infinity. However, we are told we have a solid lead sphere\text{\underline{solid lead sphere}}, which means that we can increase the temperature only to the melting point of lead, which is T=328 CT=328^{\circ}~\mathrm{C}=601 K.

Having said this, we now need to substitute the area of the sphere: for a diameter DD, the area of a sphere is

A=πD2A=\pi D^2

Substituting, we get the maximum radiated power to be

P=eσπD2T4P=e\sigma \pi D^2T^4

Substituting the numerical values, we can find

P=15.67108π0.126014=232 WP=1\cdot 5.67\cdot 10^{-8}\cdot \pi \cdot 0.1^2\cdot 601^4=\boxed{232~\mathrm{W}}

Create an account to view solutions

By signing up, you accept Quizlet's Terms of Service and Privacy Policy
Continue with GoogleContinue with Facebook

Create an account to view solutions

By signing up, you accept Quizlet's Terms of Service and Privacy Policy
Continue with GoogleContinue with Facebook

Recommended textbook solutions

Physics for Scientists and Engineers: A Strategic Approach with Modern Physics 4th Edition by Randall D. Knight

Physics for Scientists and Engineers: A Strategic Approach with Modern Physics

4th EditionISBN: 9780133942651 (5 more)Randall D. Knight
3,508 solutions
Physics for Scientists and Engineers 9th Edition by John W. Jewett, Raymond A. Serway

Physics for Scientists and Engineers

9th EditionISBN: 9781133947271 (2 more)John W. Jewett, Raymond A. Serway
6,057 solutions
Physics for Scientists and Engineers with Modern Physics 10th Edition by John W. Jewett, Raymond A. Serway

Physics for Scientists and Engineers with Modern Physics

10th EditionISBN: 9781337553292 (7 more)John W. Jewett, Raymond A. Serway
3,196 solutions
Classical Mechanics 1st Edition by John R. Taylor

Classical Mechanics

1st EditionISBN: 9781891389221 (5 more)John R. Taylor
741 solutions

More related questions

1/4

1/7