A cylinder is a simple geometric shape made up of two parallel circular bases of equal size. If you want to know how to calculate the volume, you are in the right place; all you need is to know its height (h) and the radius of one of the two bases (r). The formula to use is the following: V = hπr2. Find out what are the steps to follow.
Steps
Method 1 of 1: Calculate the Volume of a Cylinder
Step 1. Find the radius of the circular base
Both cylinder bases are the same size. If you already know the radius measurement you can go directly to the next step. If not, take a simple ruler to measure the two furthest points on one of the two circles and then divide the result by two. This method allows you to get more accurate data than directly measuring the radius of the base of your cylinder. Let's assume that the radius measures 1 cm. Take note.
- If you already know the diameter of the base, you just need to divide it by 2.
- If you know the measurement of the circumference of the base, divide it by 2π and you will get the measurement of the radius.
Step 2. Calculate the area of the circular base
To do this, use the mathematical formula to calculate the area of a circle: A = πr2. Substitute "r" for the radius measurement of your cylinder and that's it! Here's what you'll get in our case:
- A = π x 12 =
- A = π x 1.
- Approximating the value of π to 3.14 you will find that the area of the base of your cylinder is equal to 3.14 cm2.
Step 3. Measure the height of the cylinder
If you already know this value go to the next step. If not, use the ruler and measure the distance between the edges of the two bases. Let's imagine that the height measures 4 cm. Take note.
Step 4. Multiply the area of the base by the height
Imagine that the volume of a cylinder is made up of the sum of the areas of the circles extending from the lower base to the upper one. Already knowing the value of the area of one of these circles, 3, 14 cm2, and the height, 4 cm, the final result will be given by the product of these two values. V = 3.14 cm2 x 4 cm = 12.56 cm3. This is the final answer to your problem.
Always indicate volume with a cubic unit of measurement, since it represents a surface that extends in three dimensions of space
Advice
- Once you have calculated the area of the circle you can multiply it by the height, imagining stacking many circles (identical to the base of your cylinder) one on top of the other, until you reach the overall height. Since you already know the area value of a single circle, the result will be the volume of your cylinder.
- Make up some practice problems so that you are prepared when you really need to calculate the volume of a cylinder.
- Remember that the diameter represents the longest chord that can be inscribed in a circle or circumference. In other words, it is the greatest distance existing between two points located on the circumference of a circle. Then, fix your ruler's "0" value to a point on the circumference and the largest measurement you get, without moving the "0" point of the ruler, will be the diameter of the circle.
- Make sure you take accurate measurements.
- It's easier using a calculator.
- To get the radius measurement easier and more accurate, measure the diameter of the base and divide it by 2 instead of looking for the exact center of the circle.
