(i) Diameter, d = 14 cm
Radius, r = \(\frac{14cm}{2}\) = 7cm
Surface area of a sphere = \(4\pi r^2\)
= 4 × \(\frac{22}{7}\) × 7cm × 7cm
= 616 cm2
(ii) Diameter, d = 21 cm
Radius, r = \(\frac{21cm}{2}\)
Surface area of a sphere = \(4\pi r^2\)
\(= \frac{4}{2} × \frac{22}{7} × \frac{21}{2} × \frac{21}{2}\)
= 1386 cm2
(iii) Diameter, d = 3.5 m
Radius, r =\( \frac{3.5}{2}\) = 1.75m
Surface area of a sphere = \(4\pi r^2\)
= 4 × \(\frac{22}{7} \)× 1.75m x 1.75m
= 38.5 m2
The surface area of a sphere with diameters 14 cm, 21 cm, and 3.5 m are 616 cm2, 1386 cm2, and 38.5 m2 respectively.
A driver of a car travelling at \(52\) \(km \;h^{–1}\) applies the brakes Shade the area on the graph that represents the distance travelled by the car during the period.
Which part of the graph represents uniform motion of the car?