A sphere is a ball-shaped object. A hemisphere is half of a sphere.
e.g.
There is one key measurement for a sphere, that is the radius, r.
Volume and Surface Area of a Sphere
The volume and surface area of a sphere are found using two formulae.
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Volume V = 4⁄3 π r3
Surface Area S = 4 π r2
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Examples of Sphere Calculations
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Examples
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Calculation
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Find the volume of the sphere below.
Use π = 3.1 |
The radius of the sphere is 5 cm. V = 4⁄3 π r3 V = 4⁄3 × 3.1 × 53 V = 516.7 cm3 (to 4 sig. fig.)
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For the sphere shown above, find the surface area. Use π = 3.1 |
Surface area = 4π r2 Surface area = 4 × 3.1 × 52 Surface area = 310 cm2 |
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A sphere has a volume of 900 cm3, what is its radius? |
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