What is the surface area of a spherical pot whose radius is 4.2 cm ? (Take π = \(\frac{22}{7}\))
221.76 cm2
The correct answer is 221.76 cm 2.
The formula 4\pi r^2 was first discovered by Archimedes. He famously showed that the surface area of a sphere is equal to the lateral surface area of a circumscribed cylinder (a cylinder that perfectly encloses the sphere) excluding its bases. Understanding surface area is important in various applications, such as calculating the amount of material needed to cover a spherical object, determining heat transfer, or studying properties of bubbles and droplets.
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