In this beginner’s guide, we’ll explain what a cross-sectional area is and how to calculate it. We’ll also show you how the cross-sectional area calculator works and give examples of how to use it.

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What is a cross-section and how to calculate a cross-sectional area?

A cross-section is a cut through an object, in a direction perpendicular to the object’s length. The cross-sectional area of an object is the area of the object in a particular plane. For example, if you were to take two planks of wood and place them against each other with their edges touching, you would have created a cross-sectional view of your two planks. The actual area of each individual plank can be calculated as well as how much space they occupy together when placed together at right angles like this.

How to find the cross-sectional area?

  • Area of Rectangle: A rectangle is a quadrilateral with four right-angles. The length and width are called its sides.
  • Area of Circle: Circumference = π * diameter
A = π *\times r^2

  • Area of Triangle: If you know the base (b) and height (h), use the Pythagorean theorem, which states that in any right triangle, the square of the hypotenuse is equal to the sum of squares on the other two sides. This means that for a triangle with legs b and h, you can find its area by multiplying base times height times 1/2.
  • Area of Trapezoid: A trapezoid has two parallel sides but does not have exactly two parallel bases as well; this makes calculating its area more difficult than it would be if both sides were parallel or both bases were parallel because there are more unknowns than equations available to solve for them all simultaneously! Still, there is a way around this problem if you’re feeling brave enough! We’ll look at how later on when we discuss calculating A T r(a).

Example: Using the cross-sectional area calculator

You can use the cross-sectional area calculator to find the area of a cross-section. The calculator accepts measurements in either metric (SI) or imperial units.

How To Use It:

  • Type in your measurements into the boxes provided and click “Calculate”. If you would prefer to use another measurement system, select it from the drop-down menu at the top left of the page.
  • Once your measurements are entered, you’ll see an answer displayed on the screen – that’s it! The answer is automatically converted into whatever unit system you first selected using our handy conversion tools at the top left of the page.

Applications of cross-section shapes

You can use the cross-sectional area to calculate the moment of inertia for a solid object. The moment of inertia is the measure of an object’s resistance to rotational acceleration. In other words, it’s how much force you need to apply at any point in order to make the object rotate around that point. If you have a big barbell and want to lift it off your bench, you’re better off grabbing onto one end than trying to lift from all sides at once. That’s because when each side has its own rotation axis, there are more possible directions for the barbell (and thus more possible directions for potential torque).

Hence why it helps if your tires are wide enough: they give more surface area over which your car can grip pavement instead of sliding out from underneath you during cornering maneuvers like lane changes or turns into driveways (ahem).


What is the maximum cross-sectional area?

The area of the maximum cross-section is also taken to mean the area of the body’s projection onto a plane perpendicular to the direction of its motion.

What is the minimum cross-sectional area?

The cross-sectional area was a minimum at sections perpendicular to the longitudinal axis of the girder through the centers of the large circular holes.

Is cross-sectional area the same as diameter?

Well, the diameter of this circle is the diameter of the conductor, while the area of the circle is what is known as the cross-section of the conductor.