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A sphere of surface area 500𝝅 square centimeters is cut into two equal hemispheres. The surface area of each hemisphere in square centimeters is

A250𝝅

B500𝝅

C375𝝅

D125𝝅

Answer:

C. 375𝝅

Read Explanation:

Sphere and Hemisphere Surface Area Calculations

Sphere Properties

  • The surface area of a sphere is given by the formula A = 4πr², where 'r' is the radius.

  • Given surface area of the sphere is 500π square centimeters.

  • Therefore, 4πr² = 500π.

  • Solving for r²: r² = 500π / 4π = 125.

  • Thus, the radius 'r' of the sphere is √125 cm.

Hemisphere Properties

  • When a sphere is cut into two equal hemispheres, each hemisphere has two surfaces:

    1. The curved surface area, which is half the surface area of the original sphere.

    2. The flat circular base area, which is created by the cut.

  • Curved surface area of one hemisphere = (1/2) × (Surface area of sphere) = (1/2) × 500π = 250π square centimeters.

  • Area of the circular base = πr².

  • From the sphere's calculation, we found r² = 125.

  • So, the area of the circular base = 125π square centimeters.

  • Total surface area of one hemisphere = Curved surface area + Area of circular base

  • Total surface area = 250π + 125π = 375π square centimeters.


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