Question

what is perimeter of circle​

Answer 1

Question-

What is the perimeter of a circle?

Answer-

A perimeter of any shape is the total length of the edges of the shape. Simply put, it is the length of the boundary of a shape. In a triangle, it would be the total length of the three sides. In ta square, it would be the total length of the four sides. Similarly in a circle, it is the length of its one edge.

Formulae for calculating the perimeter of a circle-

2πr or πd

Where,

r = radius of the circle

d = diameter of the circle.

Derivation of the formulae of the perimeter of a circle-

Proving that the ratio of the circumference to the diameter is fixed for any circle:

This is quite easy to prove because all circles are similar.

Consider two small arcs AB and CD of two circles of radii x and y units, both of which make an angle of measure θ at the centers P and Q respectively.

For smaller values of θ, the arc length$\overset\frown{AB}$ is almost equal to the length of the line segment $\overline{AB} . Similarly, \overset\frown{CD} ≈ \overline{CD}$ . Since the angle θ is the same in both the triangles APB and CQD, and the ratio AP : PB = CQ : QD = 1 : 1, using the SAS rule of triangle similarity, ΔAPB is similar to ΔCQD. Therefore, It follows that AB : AP = CD : CQ.

In other words, for all values of the angle θ, the ratios $\overset\frown{AB} :$$AP and \overset\frown{CD}$ : CQ are equal. It follows that the ratio circumference : radius, which is equivalent to saying the ratio circumference : diameter is constant for any circle.

If this constant is equal to some number π, then circumference = π × diameter, or circumference = 2π × radius. Hence proved.

Answer 2

Answer:

Hey This Is Ur Ans

Formula for calculating the perimeter of a circle-

2πr or πd

Where,

r = radius of the circle

d = diameter of the circle.

Hope It's Helpful For U ☺️