Surface Area And Volume Of Spheres - SS3 Mathematics Past Questions and Answers - page 1
A sphere has a diameter of \(14\ cm\). Calculate its surface area. \((\pi = \frac{22}{7})\)
\(540cm^{2}\)
\(440cm^{2}\)
\(610cm^{2}\)
\(616cm^{2}\)
\[Surface\ area\ of\ a\ sphere = 4\pi r^{2}\]
\[diameter = 14cm\ \therefore radius = 7cm\ \]
\(Surface\ area\ of\ a\ sphere = 4 \times \frac{22}{7} \times \frac{7^{2}}{1} = 616cm^{2}\)
A sphere has a diameter of \(14\ cm\). Calculate its volume. \((\pi = \frac{22}{7})\)
\(6160cm^{3}\)
\(1437.33cm^{3}\)
\(1700cm^{3}\)
\(2025.25cm^{3}\)
\[Volume\ of\ a\ sphere = \ \frac{4}{3}\pi r^{3}\]
\[diameter = 14cm\ \therefore radius = 7cm\]
\(Volume\ of\ a\ sphere = \ \frac{4}{3} \times \frac{22}{7} \times 7^{3} = 1,437.33{cm}^{3}\)
Given that the radius of the earth is \(6,371\ km\), calculate the surface area of the earth.
\[Surface\ area\ of\ a\ sphere = 4\pi r^{2}\]
\[radius = 6,371\ km\ \]
\[Surface\ area\ of\ a\ sphere = 4 \times \frac{22}{7} \times \frac{{6,371}^{2}}{1} = 510,269,773\ km^{2}\]