📘 Volume of Cylinder – Formula, Examples & Applications
When you look at a can of soda, a gas cylinder, or even a water pipe, you’re actually looking at a cylinder—a three-dimensional geometric shape. In mathematics, calculating the volume of a cylinder is a key concept taught from Class 8 onwards because it’s used in everyday scenarios and higher studies in geometry, physics, and engineering.
🔍 What is a Cylinder?
A cylinder is a 3D solid with two parallel circular bases and one curved surface connecting them. It looks like a tube or a pipe. The distance between the two bases is called the height (h), and the radius of the base is r.
📐 Volume of Cylinder Formula
The standard formula to find the volume of a cylinder is:
Volume = π × r² × h
Where:
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π (pi) ≈ 3.14159
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r = radius of the circular base
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h = height of the cylinder
This formula gives the volume in cubic units (like cm³, m³, or in³), which tells you how much space is inside the cylinder.
✏️ Example Calculation
Let’s calculate the volume of a cylinder with:
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Radius (r) = 5 cm
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Height (h) = 10 cm
Using the formula:
Volume = π × 5² × 10 = π × 25 × 10 = 250π ≈ 785.4 cm³
So, the volume of the cylinder is 785.4 cubic centimeters.
🧠 Why Understanding Volume of Cylinder is Important
Knowing how to calculate the volume of cylinder is essential for:
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Solving real-world problems (e.g., how much liquid a tank can hold)
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Academic exams in maths and science
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Engineering design and architecture
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Everyday tasks like measuring container capacity
📊 Units of Volume
Depending on the size and context, the volume of a cylinder may be measured in:
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Cubic centimeters (cm³)
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Cubic meters (m³)
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Liters (L) — 1,000 cm³ = 1 L
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Cubic inches (in³)
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Gallons (in US customary system)
📎 Tips to Remember
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Always square the radius before multiplying by height.
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Keep units consistent throughout the calculation.
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Use π = 22/7 if the question instructs, or π = 3.14 for quick estimations.
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Don’t forget to include units in your final answer.
🧪 Applications in Real Life
The volume of cylinder is used in:
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Calculating capacity of water tanks and pipes
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Designing fuel tanks and storage drums
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Manufacturing cans, containers, and tubes
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Understanding chemical volume in test tubes and cylinders
💡 Practice Questions
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Find the volume of a cylinder with r = 7 cm and h = 14 cm.
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A cylindrical tank has a radius of 2 meters and height of 5 meters. What is its volume in liters?
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If the volume of a cylinder is 314 cm³ and the height is 4 cm, find the radius.
🧮 Volume of Hollow Cylinder
If you’re dealing with a hollow cylinder (like a pipe), the volume is:
Volume = π × h × (R² − r²)
Where:
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R = outer radius
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r = inner radius
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h = height
This is useful in plumbing, construction, and mechanical design.
🧾 Conclusion
Mastering the volume of cylinder formula is a must-have skill for students and professionals alike. Whether you’re solving exam questions or figuring out the size of a tank, this knowledge is both practical and empowering. Keep practicing problems with different units and scenarios to build a strong foundation.