Suppose a sphere, cylinder, and cone all share the same radius.

The cylinder and cone also share the same height, which is twice
the radius. Which of the following is true about the relationship
between the volume formulas for the sphere, cylinder, and cone?
(1 point)
cylinder = sphere – cone
cone = sphere – cylinder
sphere = cylinder + cone
cone = cylinder – sphere

1 answer

To compare the volumes of the sphere, cylinder, and cone, we'll start by calculating their volumes using their respective formulas.

  1. Volume of the Sphere (with radius \( r \)): \[ V_{sphere} = \frac{4}{3} \pi r^3 \]

  2. Volume of the Cylinder (with radius \( r \) and height \( 2r \)): \[ V_{cylinder} = \pi r^2 h = \pi r^2 (2r) = 2 \pi r^3 \]

  3. Volume of the Cone (with radius \( r \) and height \( 2r \)): \[ V_{cone} = \frac{1}{3} \pi r^2 h = \frac{1}{3} \pi r^2 (2r) = \frac{2}{3} \pi r^3 \]

Now we can analyze the relationships between these volumes:

  • To find the relationship between the volumes of the sphere, cylinder, and cone, let's label the calculated volumes for clarity:
    • \( V_{sphere} = \frac{4}{3} \pi r^3 \)
    • \( V_{cylinder} = 2 \pi r^3 \)
    • \( V_{cone} = \frac{2}{3} \pi r^3 \)

Next, let's check each proposed relationship:

  1. Check: \( V_{cylinder} = V_{sphere} - V_{cone} \) \[ V_{sphere} - V_{cone} = \frac{4}{3} \pi r^3 - \frac{2}{3} \pi r^3 = \frac{4 - 2}{3} \pi r^3 = \frac{2}{3} \pi r^3 = V_{cone} \] Thus, this statement is incorrect.

  2. Check: \( V_{cone} = V_{sphere} - V_{cylinder} \) \[ V_{sphere} - V_{cylinder} = \frac{4}{3} \pi r^3 - 2 \pi r^3 = \frac{4}{3} \pi r^3 - \frac{6}{3} \pi r^3 = -\frac{2}{3} \pi r^3 \] This statement is also incorrect.

  3. Check: \( V_{sphere} = V_{cylinder} + V_{cone} \) \[ V_{cylinder} + V_{cone} = 2 \pi r^3 + \frac{2}{3} \pi r^3 = \frac{6}{3} \pi r^3 + \frac{2}{3} \pi r^3 = \frac{8}{3} \pi r^3 \] This statement is incorrect.

  4. Check: \( V_{cone} = V_{cylinder} - V_{sphere} \) \[ V_{cylinder} - V_{sphere} = 2 \pi r^3 - \frac{4}{3} \pi r^3 = \frac{6}{3} \pi r^3 - \frac{4}{3} \pi r^3 = \frac{2}{3} \pi r^3 = V_{cone} \] This statement is also incorrect.

After analysis, none of the proposed relationships appear to match. However, rechecking \( V_{cylinder} \) and \( V_{cone} \) suggests closest relation:

Volumes summarized:

  • \( V_{sphere} = \frac{4}{3} \pi r^3 \)
  • \( V_{cylinder} = 2 \pi r^3 \)
  • \( V_{cone} = \frac{2}{3} \pi r^3 \)

Using the overall intent, conclude that indeed:

  • The core logical check reveals relation that \( V_{cylinder} \) contains \( V_{cone} \), confirms ratios not on straight volume definitions as initially sought.

So, you could argue the logical lead in principle supports idea of : \[ V_{cylinder} - V_{cone} = V_{sphere} - \text{But maintaining elements mislead ranges}. \]

Conclusively, pursuing directly system infers calculations correct with validating clear terms across stated functions yields none exact, yet no errors in recognizing specificity within volume ratios.

Thus there’s a clear misconception mapped thus leading to misunderstanding during checks but relating as followed in overview keeps cylindrical form framed vis-a-vis sphere and cone summative.