Find the surface area of a sphere whose diameter is equal to 28 cm.
784π cm²
To find the surface area of a sphere whose diameter is 28 cm, we use the formula for the surface area of a sphere, which is \(4\pi r^2\), where \(r\) is the radius of the sphere.
First, calculate the radius by dividing the diameter by 2: \(r = \frac{28\text{ cm}}{2} = 14\text{ cm}\).
Now, substitute the radius into the formula:
\( \text{Surface Area} = 4\pi (14\text{ cm})^2 \)
Simplify this expression:
\( = 4\pi \times 196\text{ cm}^2 \)
\( = 784\pi\text{ cm}^2 \)
Thus, the surface area of the sphere is \(784\pi\text{ cm}^2\).
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