A cone is placed inside a cylinder. The cone has half the radius of the cylinder, but the height of each figure is the same. The cone is tilted at an angle so its peak touches the edge of the cylinder's base. What is the volume of the space remaining in the cylinder after the cone is placed inside?

A. [tex]\frac{3}{4} \pi r^2 h[/tex]
B. [tex]\frac{2}{3} \pi r^2 h[/tex]
C. [tex]\frac{11}{12} \pi r^2 h[/tex]
D. [tex]\frac{5}{8} \pi r^2 h[/tex]
E. [tex]\frac{1}{2} \pi r^2 h[/tex]



Answer :

To solve the problem of finding the volume of the remaining space in the cylinder after the cone is placed inside, let's follow these steps in detail:

1. Determine the volume of the cylinder:

The volume [tex]\( V_{\text{cylinder}} \)[/tex] of a cylinder with radius [tex]\( r \)[/tex] and height [tex]\( h \)[/tex] is given by the formula:
[tex]\[ V_{\text{cylinder}} = \pi r^2 h \][/tex]

2. Determine the volume of the cone:

The volume [tex]\( V_{\text{cone}} \)[/tex] of a cone with the same radius [tex]\( r \)[/tex] and height [tex]\( h \)[/tex] is given by the formula:
[tex]\[ V_{\text{cone}} = \frac{1}{3} \pi r^2 h \][/tex]

3. Calculate the volume of the remaining space:

The volume of the space remaining in the cylinder after placing the cone inside is the difference between the volume of the cylinder and the volume of the cone:
[tex]\[ V_{\text{remaining}} = V_{\text{cylinder}} - V_{\text{cone}} \][/tex]
Plugging in the formulas for [tex]\( V_{\text{cylinder}} \)[/tex] and [tex]\( V_{\text{cone}} \)[/tex]:
[tex]\[ V_{\text{remaining}} = \pi r^2 h - \frac{1}{3} \pi r^2 h \][/tex]
Simplify the expression:
[tex]\[ V_{\text{remaining}} = \left( \pi r^2 h \right) - \left( \frac{1}{3} \pi r^2 h \right) \][/tex]
[tex]\[ V_{\text{remaining}} = \pi r^2 h \left( 1 - \frac{1}{3} \right) \][/tex]
[tex]\[ V_{\text{remaining}} = \pi r^2 h \left( \frac{3}{3} - \frac{1}{3} \right) \][/tex]
[tex]\[ V_{\text{remaining}} = \pi r^2 h \left( \frac{2}{3} \right) \][/tex]
[tex]\[ V_{\text{remaining}} = \frac{2}{3} \pi r^2 h \][/tex]

4. Match the result with the given choices:

The volume of the space remaining in the cylinder is:
[tex]\[ \boxed{\frac{2}{3} \pi r^2 h} \][/tex]

Therefore, the correct answer is:
[tex]\[ \boxed{B. \frac{2}{3} \pi r^2 h} \][/tex]