A cylinder and a cone have the same volume. The cylinder has radius x
and height y
. The cone has radius 3x
. Find the height of the cone in terms of y
.














Respuesta :

The height of the cone in terms of y would be

H=4y/3
SEE WORK BELOW:

V=∏x2y
cone
V=(1/3)∏(3x/2)2H where H=height of the cone
solve for H
set the volumes equal to each other
∏x2y=(1/3)∏(3x/2)2H
divide both sides by ∏
x2y=(1/3)(3x/2)2H
x2y=(1/3)(9x2/4)H
x2y=(3x2/4)H
x2y=(3/4)x2H
divide both sides by x2
y=(3/4)H
multiply both sides by (4/3)
(4/3)y=H
H=4y/3 or H=(4/3)y, either way, is the height of the cone

Answer: [tex]h = \frac{y}{3}[/tex]

Step-by-step explanation:

The formula for calculating the volume of a cylinder is given as :

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

The formula for calculating the volume of a cone is given as :

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

Since the cylinder and the cone have the same volume according to the question , we will equate the two formulas, that is:

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

substituting the values of r , we have

[tex]\pi x^{2} y=\frac{1}{3}\pi (3x)^{2}h[/tex]

[tex]\pi x^{2} y=\frac{1}{3}\pi (9x^{2} )h[/tex]

since [tex]\pi x^{2}[/tex] is common to both sides , it will cancel out , that is

[tex]y = \frac{1}{3}(9)h[/tex]

[tex]3y = 9h[/tex]

divide through by 9

[tex]3y/9 = h[/tex]

Therefore , the height of the cone in terms of y is

[tex]h = \frac{y}{3}[/tex]