Formula for Volume of a Cuboid
Learning text on the topic Formula for Volume of a Cuboid
Understanding the Volume of a Cuboid
In our daily lives, we often come across objects shaped like cuboids (or rectangular prisms) - think of boxes, bricks or even parts of buildings. A prism is defined as a 3D shape with a constant cross section. A rectangular prism is a 3D shape with six faces, each one a rectangle. When we talk about the volume of a rectangular prism using cubic units, we find out how much space it takes up. It's like figuring out how much water can fill a fish tank or how many books you can pack into a box. This volume helps us understand the capacity of these objects in cubic units, which measure space in three dimensions.
Volume Formula: The volume of a rectangular prism is calculated by multiplying its length ($l$), width ($w$) and height ($h$). The formula is $V = l \times w \times h$.
Formula for Volume of a Rectangular Prism
In maths, we often have more than one way to solve a problem, and that's true for finding the volume of a rectangular prism too.
The formula $V = l \times w \times h$ directly multiplies the prism's dimensions. This method is straightforward and effective for calculating volume.
Let’s learn how to find the volume of a cuboid with this formula.
A cuboid has a length of $4$ cm, width of $3$ cm and height of $6$ cm. Calculate its volume.
- Length ($l$) = $4$ cm
- Width ($w$) = $3$ cm
- Height ($h$) = $6$ cm
- Volume = $l \times w \times h = 4 \times 3 \times 6 = 72$ cm$^3$
The volume of this cuboid is $72$ cubic centimetres.
We use cubic units for units of volume because volume measures three-dimensional space. Think of stacking little blocks inside a box - you're filling it lengthwise, widthwise and heightwise. So, we multiply these three dimensions, and the result is in cubic units, like filling a box with tiny cubes.
Find the volume of a cuboid with a length of 5 m, a width of 2 m and a height of 3 m.
- Length ($l$) = $5$ m
- Width ($w$) = $2$ m
- Height ($h$) = $3$ m
- Volume = $l \times w \times h = 5 \times 2 \times 3 = 30$ m$^3$
The volume of this cuboid is $30$ cubic metres.
Use the formula for the volume of a cuboid, and solve these examples on your own!
Finding the Volume of a Prism with $V=Bh$
Another formula to find the volume of a rectangular prism, or cuboid, is using $V = B \times h$. Here, $B$ represents the area of the base of the shape. For a rectangular prism, this base is the area of the rectangle at the bottom. This formula is really helpful, not just for rectangular prisms, but also for other 3D shapes like cylinders which have a circular base (volume of a cylinder). It helps us understand how much space these shapes occupy by considering their base area and height.
Let's calculate the volume of a cuboid with a length of 4 feet, a width of 3 feet and a height of 6 feet.
Determine the dimensions of the cuboid:
- Length ($l$) = $4$ ft
- Width ($w$) = $3$ ft
- Height ($h$) = $6$ ft
Calculate the base area (B):
- The base area is found by multiplying the length and width.
- Base Area ($B$) = $l \times w = 4 \times 3 = 12$ square feet.
Calculate the volume using $V = B \times h$:
- Now, multiply the base area by the height.
- Volume ($V$) = $B \times h = 12 \times 6 = 72$ cubic feet.
The volume of this cuboid is $72$ cubic feet.
Practise using this formula on your own!
Formula for Volume of a Cuboid – Application
Solving problems involving the volume of a cuboid, or rectangular prism, enhances our understanding of space and capacity. It applies in diverse fields, from architecture and construction to everyday tasks like packing or storage.
Formula for Volume of a Cuboid – Summary
Key Learnings from this Text:
- Understanding the volume of a cuboid helps in calculating space in practical situations.
- The volume formula, $V = l \times w \times h$, is straightforward and widely applicable.
- Alternative method: $V = B \times h$, where $B$ is the base area, deepens conceptual understanding.
- Real-world application of this knowledge spans from storage organisation to construction planning.
Formula | Explanation |
---|---|
$V = l \times w \times h$ | Multiply length ($l$), width ($w$) and height ($h$) to find the volume. |
$V = B \times h$ | Calculate the base area ($B$ = length x width), then multiply by height ($h$). |
Formula for Volume of a Cuboid – Frequently Asked Questions
Formula for Volume of a Cuboid exercise
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Find the volume of the cuboid.
HintsTo calculate the volume, multiply the length, width and height.
We need to solve $10 \times 5 \times 5$.
$5 \times 5 = 25$.
Multiply this by $10$.
SolutionThe volume of this cuboid is $250 cm^3$.
The length is $10 cm$, the width is $5 cm$ and the height is $5 cm$.
Multiply these together: $10 \times 5 \times 5 = 250$.
Therefore, the correct answer is $250 cm^3$.
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Calculate the volume.
HintsThe length is 4 cubes long.
Count the cubes to find the width and height.
Once you have the three measurements, multiply them together.
Multiply $4 \times 2 \times 2$.
SolutionThe length is 4 units, the width is 2 units and the height is 2 units.
Multiply $4 \times 2 \times 2$ to get the volume, $16$ units $^3$.
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Can you label the cuboid?
HintsThe height is the distance from the base to the top, the length is how long the cuboid is, and the width is perpendicular to the length.
The formula to calculate the volume is $V= l \times w \times h$.
Remember, volume is measured in cubic units such as $cm^3$.
Once you have found the measurement of the total volume, work backwards to find the other measurements.
SolutionThe length is $2 cm$, the width is $2 cm$ and the height is $10 cm$.
When we multiply $10 \times 2 \times 2$, we get the total volume of the cuboid, $40 cm^3$.
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Find all of the prisms with a volume of 48 centimetres cubed.
HintsFind the volume using the formula $V= l \times w \times h$.
There are three cuboids with a volume of $48 cm^3$.
SolutionThese three cuboids have a volume of $48 cm^3$.
- $2 \times 2 \times 12 = 48 cm^3$
- $8 \times 2 \times 3 = 48 cm^3$
- $4 \times 4 \times 3 = 48 cm^3$
The volumes of the other two cuboids are:
- $10 \times 3 \times 4 = 120 cm^3$
- $3 \times 3 \times 6 = 54 cm^3$
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Which are the formulas used to find the volume of a cuboid?
HintsThere are two formulas used to calculate the volume of a cuboid.
One way to find the volume is to multiply the base times the height, where the base is the length times the width.
Use this list to help you:
- $V$ = volume
- $A$ = area
- $l$ = length
- $w$ = width
- $h$ = height
- $b$ = base
SolutionTo find the volume of a rectangular prism, use:
- $V = b \times h$
- $V = l \times w \times h$
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Can you order the cuboids?
HintsUse the formula $V= l \times w \times h$ to find the volume of each. Then sort from smallest to largest.
Start by calculating the volume of the purple cuboid. Multiply $7 \times 7 \times 7$.
These cuboids have measurements in inches, so the volume will be in inches cubed.
SolutionUse the formula $V= l \times w \times h$ to find the volume of each. Then sort from smallest to largest.
- The volume of the red prism = $4 \times 6 \times 3 = 72 in^3$.
- The volume of the blue prism = $5 \times 2 \times 8 =80 in^3$.
- The volume of the orange prism = $2 \times 10 \times 5.5 =110 in^3$.
- The volume of the purple prism = $7 \times 7 \times 7 =343 in^3$.
So, the shapes from smallest to largest are red, blue, orange, purple.