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Given a sphere with radius r, the formula 4pi r^2 gives

A. the volume
B. the surface area
C. the radius
D. the cross-sectional area

Given a sphere with radius r, the formula 4pi r^2 gives A. the volume B. the surface-example-1

2 Answers

4 votes

Final answer:

The formula 4π r^2 is the formula for calculating the surface area of a sphere, not its volume, radius, or cross-sectional area.

Step-by-step explanation:

The formula 4π r^2 corresponds to the surface area of a sphere with radius r. This can be differentiated from the volume formula for a sphere, which is ⅔(π)(r)³. The formula for the volume of a cube is (s)³ and for the surface area of a cube is 6(s)². Therefore, when discussing the surface area and volume of a sphere, clarity is essential to avoid mixing these up with the formulas for a cube.

When tasked with remembering formulas from geometry, it can be helpful to revert to fundamental geometric principles. For example, a cylinder's volume can be thought of as the area of the circular base multiplied by the height of the cylinder, which reflects a combination of circular and rectangular geometries.

In summary, the given formula, 4π r^2, should not be confused with volume calculations or the dimensions of other shapes such as cubes or cylinders. Instead, it precisely represents the surface area of a sphere.

User Strubbl
by
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3 votes

Answer:

Step-by-step explanation:

That's B: the surface area.

The volume of the sphere is V = (4/3)πr³; A = 4πr² happens to be the derivative of V with respect to r.

User Nimit Dudani
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3.8k points