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I need to find the surface area. it's a cut sphere with a diameter of 14.

I need to find the surface area. it's a cut sphere with a diameter of 14.-example-1
User Agold
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1 Answer

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Given data:

The diameter of the cut sphere, D=14 in.

The radius of the cut sphere is,


\begin{gathered} r=(D)/(2) \\ r=(14)/(2) \\ r=7\text{ in} \end{gathered}

The cut sphere is called a hemisphere.

The surface area of a sphere is


A_1=4\pi r^2

So, the lateral surface area of a hemisphere is half the surface area of sphere. Therefore, the lateral surface area of a hemisphere is,


\begin{gathered} A_2=(4\pi r^2)/(2) \\ A_2=2\pi r^2 \end{gathered}

The hemisphere has a lateral surface and a circular surface. The area of the circular surface is,


A_3=\pi r^2

Therefore, the total area of the hemisphere is,


\begin{gathered} A=A_2+A_3 \\ A=2\text{ }\pi r^2+\pi r^2 \\ A=3\text{ }\pi r^2 \end{gathered}

The total surface area of a hemisphere is,


\begin{gathered} A_{}=3\text{ }\pi r^2 \\ A=3\text{ }\pi*7^2 \\ A=461.8in^2 \end{gathered}

Therefore, the total surface area of the cut sphere is 461.8 square inches.

User Amira
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