2. [5 marks] The Earth is not quite spherical. In particular, Earth's shape is
a slight oblate spheroid which has an equatorial diameter 42 km greater
than its polar diameter. Also, the tallest mountain on Earth is about 8.85
km above sea level and the deepest ocean trench (the Marianas Trench in
the Pacific Ocean) is about 11 km below sea level. Compare the scale of
these irregularities with the irregularities found on an average golf ball.
The standard diameter for a golf ball is 1.680 inches, while dimples
average about 0.0100 inches in depth. If a golf ball was scaled up to the size of the Earth, how deep
would these dimples be? Express your answer in kilometres and compare them to the height of
Earth's tallest mountain and deepest ocean trench, drawing a conclusion about the relative
smoothness of the ball and the Earth.