You are examining a log that you find on the ground. The diameter of the log is 32 inches, but the length of the log is unknown. Find the log's length if its volume is 10, 000m in.3

Round your
answer to the nearest hundredth.
(1 point)
length
in.

1 answer

To find the length of the log given its volume, we can use the formula for the volume of a cylinder:

\[ V = \pi r^2 h \]

where:

  • \( V \) is the volume,
  • \( r \) is the radius,
  • \( h \) is the height (length of the log).

Given:

  • The diameter of the log is 32 inches, so the radius \( r \) is half of that: \[ r = \frac{32}{2} = 16 \text{ inches} \]

  • The volume \( V \) is given as 10,000 cubic inches.

Rearranging the formula for height \( h \) gives us:

\[ h = \frac{V}{\pi r^2} \]

Now, substituting the values into the equation:

  1. Calculate \( r^2 \): \[ r^2 = 16^2 = 256 \text{ square inches} \]

  2. Calculate the volume with the radius: \[ h = \frac{10000}{\pi \times 256} \]

  3. Using \( \pi \approx 3.14159265359 \): \[ h = \frac{10000}{3.14159265359 \times 256} \]

  4. Calculate \( \pi \times 256 \): \[ \pi \times 256 \approx 804.247 \]

  5. Now calculate \( h \): \[ h \approx \frac{10000}{804.247} \approx 12.43 \text{ inches} \]

Thus, the length of the log is approximately 12.43 inches.