|


So, the volume
of a sphere
varies directly as the cube of its radius.
Example 12
The distance, d m, through which a cricket ball falls after
reaching its maximum altitude varies as the square of the elapsed time, t
s. The ball takes 3 seconds to fall 44.1 m. How long will it take to fall
through 78.4 m?
Solution:

Substituting for k in (1) gives:

This is the formula which relates d and t.

So, the time taken to fall through 78.4 m is 4 seconds.
|