Question

Each equal part of the circle is called:
A. Semi circle
B. Major circle
C. minor circle
D. None

Answer 1

Hint:
In a circle, a number of chords can be drawn, which divide the circle into two parts. The largest chord of a circle is the chord passing through the center, and that is known as diameter of the circle. Chords are basically line segments that join any two points on the circle. As a single chord divides the circle into two parts, so we get two arcs on the circle, namely a major arc and a minor arc.

Complete step by step solution:
If we draw a chord in a circle and then construct two line segments from the center of the circle to the endpoints of the chord, then we can measure a central angle between those two line segments. That central angle can be acute or obtuse. The arc along which the measure of a central angle is acute is called minor arc and the arc along which the measure of the central angle is obtuse is called major arc.

Now we need to find the equal part of a circle. As already discussed, any chord of a circle divides it into two parts. Now, if the chord pass through the centre of the circle i.e. of we talk about the diameter of the circle then the central angles in both the parts is \[180^\circ \]

So we see that any chords other than the diameter divide the circle into two unequal parts, whereas the diameter divides the circle into two equal parts because both of the central angles are the same on both sides i.e. \[180^\circ \]. Hence each equal part of a circle is called a semi circle.

$ \therefore $ The correct option is A. Semi Circle

Note:
Just like a chord is a line segment that connects two points on a circle, a line which cuts any two points on a circle is called secant. There are chances that students got confused between these two terms as both of them join any two points on the circle, but there is a slight difference between two as one is a line segment and the other is a line. Likewise, any line which cuts the circle on a single point is called tangent of the circle.