Table of Contents
Last modified on August 3rd, 2023
The volume of a pentagonal prism is the space it occupies in the three-dimensional plane. It is measured in cubic units such as m3, cm3, mm3, ft3.
The formula is given below:
Let us solve some examples to understand the concept better.
Find the volume of a regular pentagonal prism given in the figure.
As we know,
Volume (V) = ${\dfrac{5}{2}abh}$,, here, a = 6.193 m, b = 9 m, h = 20 m
${\therefore V= \dfrac{5}{2}\times 6.193\times 9\times 20}$
= 2786.85 m3
Finding the volume of a pentagonal prism when the BASE EDGE and HEIGHT are known
Find the volume of a regular pentagonal prism with a base edge of 4 cm and a height of 7 cm.
Here we will use an alternative formula.
Volume (V) = ${\dfrac{1}{4}\sqrt{5\left( 5+2\sqrt{5}\right) }b^{2}h}$ , here b = 4 cm, h = 7 cm
${\therefore V= \dfrac{1}{4}\sqrt{5\left( 5+2\sqrt{5}\right) }\times 4^{2}\times 7 }$
≈ 192.7 cm3
Finding the volume of an oblique pentagonal prism when the BASE EDGE and HEIGHT are known
Find the volume of the oblique pentagonal prism given in the figure.
As we know,
The volume of an oblique pentagonal prism = the volume of a right pentagonal prism having the height ‘h’
Using the alternative formula
Volume (V) = ${ \dfrac{1}{4}\sqrt{5\left( 5+2\sqrt{5}\right) }b^{2}h }$ , here b = 6 m, h = 13 m
${\therefore V= \dfrac{1}{4}\sqrt{5\left( 5+2\sqrt{5}\right) }\times 6^{2}\times 13 }$
= 805.2 m3
Last modified on August 3rd, 2023