Question

Draw any circle and mark an arc.

Answer 1

Hint: Firstly, we have to draw a circle. For this, we have to mark a point, O on the paper. Then, we have to choose a random length, say 4 cm, as radius. Take a compass with the pointer at 0 cm and measure 4 cm such that the pencil pointer is at the 4 cm. Then, we have to place the compass tip at the centre, O on the paper and rotate the compass completely to $360{}^\circ $ . An arc of a circle is any portion of the circumference of a circle.

Complete step-by-step solution:
We have to draw a circle and mark an arc. Let us recollect what a circle is. A circle is a closed two-dimensional figure in which the set of all the points in the plane is equidistant from a given point called “centre”.
Let us draw a circle. The following are the steps involved in it.
(i) Firstly, we have to mark a point, O on the paper.
(ii) We have to choose a random length, say 4 cm, as radius. Radius of a circle is the distance from the center of the circle to any point on its circumference (perimeter or distance around a circle).
(iii) We have to take a compass with the pointer at 0 cm and measure 4 cm such that the pencil pointer is at 4 cm.
(iv) We have to place the compass tip at the centre, O on the paper and rotate the compass completely to $360{}^\circ $ .

In the figure above, we can see that OP and OQ are radius of 4 cm. PQ will be the diameter of the circle which is twice the radius.
Now, we have to mark an arc on the circle. We know that an arc of a circle is any portion of the circumference of a circle.

We usually denote arc using the symbol $\overset\frown{{}}$ . Therefore, in the above figure, $\overset\frown{\text{AB}}$ is an arc.


Note: Students must be thorough with the terms associated with a circle such as diameter, radius, circumference, arc and chord. If the length of an arc is exactly half of the circle, it is known as a semicircular arc. Students may get confused with arcs and chords. Chord is the straight line joining the ends of the arc. From the below figure, we can see that AB is a chord (shown in green colour).