How Much Paint for a Hemispherical Dome Using Differentials?

maladroit
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Homework Statement



Use differentials to estimate the amount of paint needed to apply a coat of paint 0.05 cm thick to a hemispherical dome with diameter 54 m.

Homework Equations



dy=dy/dx *dx

Surface area of a hemishpere=2pi*r^2

The Attempt at a Solution



dy=4pi*r dx
dy=4pi*27 *.05
dy=16.96
 
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You want to express all of your numbers in the same units. 0.05 cm is not the same as 0.05 m.
 
genius...thank you!
 
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