Q7 of 75 Page 225

The diameter of the moon is approximately one fourth of the diameter of the earth. Find the ratio of their surface areas

Let the diameter of earth be d. Therefore, the diameter of moon will be

Radius (Earth) =


Radius (Moon) = * =


Surface Area of moon = ()2


Surface Area of Earth = ()2


Ratio =


=


=


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A right circular cylinder just encloses a sphere of radius r (see Fig. 13.22). Find

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