Area Of Circle Questions

The area of a circle is the area that a circle occupies on a two-dimensional plane. Alternately, the area of the circle is the area enclosed inside the circumference or perimeter of the circle. For measuring the area occupied by a circular field or plot, use the area of a circle formula. The area formula will also enable us to determine the circle's circumference or boundary length. There is no volume in a circle. A circle has only two dimensions and has no volume. Only the area and circumference or perimeter of a circle are defined.

What Is A Circle?

A circle is made up of a group of points that are spaced uniformly apart from its centre. A circle is a locus of a point moving around a fixed point at a defined distance from the point in mathematical terms. The circle's radius is its constant distance from the centre.

Parts Of A Circle

• Radius - The radius of a circle is the distance from the centre to a point on the periphery. It is symbolised by the letter ‘r’ or ‘R’.

• Diameter - The diameter of a circle is defined as the length of a line with its ends on the circle and passing through its centre. It is symbolised by the letter ‘d’ or ‘D’. The line dividing a circle into two equal parts is known as the diameter of the circle. We might state that the diameter is merely the circle's radius multiplied by two, this means that, D=2R. We can determine the radius of the circle if we know its diameter, for example; R=D/2.

• Circumference - The length of a circle's boundary determines its circumference. This implies that a circle's circumference and perimeter are equal. The following formula can be used to get the circumference:

Circumference= 2\pi R , and as R=D/2, additionally, circumference may be computed as: 2\pi (D/2)=\pi D

What Is The Area Of A Circle?

The measure of space enclosed within a circle's periphery is known as its area. The area that the circle occupies is that which lies within its circumference. It is also known as the total number of square units contained within that circle. The area of a circle is therefore the area that is covered by one full cycle of its radius on a two-dimensional plane.

Formulas For Calculating The Area Of A Circle

For a circle with a radius ‘R’, the radius squared and the product of pi determine the area of this circle(A). It is calculated as:

A=\pi R^{2}

The unit of area is square units. Here, the value of pi is 22/7 or 3.14

Formulas To Remember

• If the radius is known, the area of the circle is calculated as A=\pi R^{2}

• When the diameter is known, the area of a circle is calculated as A=\pi d^{2}/4

• When the circumference is known, the area of a circle is calculated as A=C^{2}/4\pi