Respuesta :
Answer:
The area of a horizontal cross section at a height is [tex]\pi\times(2-\dfrac{y}{7})^2[/tex]
Step-by-step explanation:
Given that,
Height = 14 m
Radius = 2 m
Let V be the volume of a right circular cone
We need to calculate the value of R
Using given data
[tex]\dfrac{h}{r}=\dfrac{h-y}{R}[/tex]
Put the value into the formula
[tex]\dfrac{14}{2}=\dfrac{14-y}{R}[/tex]
[tex]7R=14-y[/tex]
[tex]R=2-\dfrac{y}{7}[/tex]
We need to calculate the area of a horizontal cross section at a height y
Using formula of area
[tex]A=\pi R^2[/tex]
Put the value into the formula
[tex]A=\pi\times(2-\dfrac{y}{7})^2[/tex]
Hence, The area of a horizontal cross section at a height is [tex]\pi\times(2-\dfrac{y}{7})^2[/tex]
The area of the circular cone at height y can be derived as a function, A,
having y as the input variable.
Correct response:
[tex]Area \ of \ horizontal \ cross \ section \ at \ height \ y \ is \ \underline{ A = \pi \times \dfrac{\left(14 - y\right)^2}{7} }[/tex]
Method used for deriving the area
The given parameters are;
Shape of figure = Right circular cone
Height of the cone, h = 14
Base radius, R = 2
Required:
The area of a cross section at a height y using similar triangles
Solution:
We have using similar triangles;
[tex]\mathbf{\dfrac{h}{h - y} }= \dfrac{R}{r} [/tex]
Which gives;
[tex]\mathbf{\dfrac{14}{14 - y}} = \dfrac{2}{r} [/tex]
Therefore;
2·(14 - y) = 14·r
28 - 2·y = 14·r
[tex]r = \dfrac{28 - 2 \cdot y}{14} = 2 - \dfrac{y}{7} [/tex]
The horizontal cross sectional area, A = π × r²
Therefore;
[tex]Area \ of \ the \ cross \ sectional \ area,\ A = \pi \times \left(2 - \dfrac{y}{7} \right) = \underline{ \pi \times \dfrac{\left(14 - y \right)^2}{7} }[/tex]
Learn more about a circular cone here:
https://brainly.com/question/2986448
