If the height of the cone is 5 cm and the volume is 500 cm^3, what is the radius of the cone?

(1 point)
Responses

The radius is the same as a cylinder with a volume of 500/3 and the same height.

The radius is the same as a cylinder with the same volume and same height.

The radius is the same as a cylinder with a volume 500(3) and same height.

The radius is the same as a cylinder with the same volume and height of 3.

1 answer

To find the radius of the cone given its height and volume, we can use the formula for the volume of a cone:

\[ V = \frac{1}{3} \pi r^2 h \]

where \( V \) is the volume, \( r \) is the radius, and \( h \) is the height.

Given:

  • Volume (\( V \)) = 500 cm³
  • Height (\( h \)) = 5 cm

We can plug in the values into the formula:

\[ 500 = \frac{1}{3} \pi r^2 (5) \]

This simplifies to:

\[ 500 = \frac{5}{3} \pi r^2 \]

To isolate \( r^2 \), multiply both sides by \( \frac{3}{5} \):

\[ r^2 = \frac{500 \times 3}{5 \pi} \]

Calculating the right side:

\[ r^2 = \frac{1500}{5 \pi} \]

\[ r^2 = \frac{300}{\pi} \]

Now, take the square root of both sides to find \( r \):

\[ r = \sqrt{\frac{300}{\pi}} \]

Now, let's evaluate the responses from the options given:

  1. The radius is the same as a cylinder with a volume of 500/3 and the same height.

    • Not correct since the cone's volume is 500, not 500/3.
  2. The radius is the same as a cylinder with the same volume and same height.

    • True, the radius of the cone would be different from the cylinder's radius but the condition of having the same volume and height is true.
  3. The radius is the same as a cylinder with a volume of 500(3) and same height.

    • Not correct since it would imply the cylinder's volume is 1500 which is not accurate.
  4. The radius is the same as a cylinder with the same volume and height of 3.

    • Not correct; the height comparison is incorrect.

Thus, the most appropriate response is:

The radius is the same as a cylinder with the same volume and same height.