**Covid-19 has led the world to go through a phenomenal transition .**

**E-learning is the future today.**

**Stay Home , Stay Safe and keep learning!!!**

Diameter = 2 x radius

Or radius = r = d / 2.

C = 2 Πr

Or C = Π D

________________________________________________________________

1) Radius = 4 cm, find the diameter.

Diameter = 2 x radius

⇒ Diameter = 2 x 4

⇒ Diameter = 8 cm.

________________________________________________________________

2) Diameter = 6.4 cm, find the radius.

radius = r = d / 2.

⇒ radius = 6.4/2

⇒ radius = 3.2 cm

_________________________________________________________________

2)If the radius of circle is 1.5 cm then find the diameter and the circumference.

Diameter = D = 2 r

D = 2 x 1.5

D = 3 cm.

Circumference = C = &pie;D

C = 3.14 x 3

C = 9.42 cm

________________________________________________________________

Some more parts of circle are as follows:

There are two types of arcs 1) Minor arc 2) Major arc.

Here PQR is the minor arc and PR is a major arc.

As arc is a part of a circle so,

Length of major arc = 2Πr - Π rθ / 180

________________________________________________________________

1) Find the length of arc of radius 6 cm and angle formed by the two radii is 60

r = 6 cm , θ = 60

Length of a minor arc = Π rθ / 180

Length of a minor arc = ( 3.14 x 6 x 60 ) / 180

Length of arc = 6.28 cm

________________________________________________________________

2)

Area ( minor sector ) = Πr

Area ( major sector) = Πr

________________________________________________________________

r = 8 cm , θ = 30

Area of sector = Πr

Area = (3.14 x 8

Area of sector = 16.75 cm

• Circles

• Parts of Circle

• Arc and Chords

• Equal Chords of a Circle

• Arc and Angles

• Cyclic Quadrilaterals

• Tangent to Circle

**Covid-19 has affected physical interactions between people.**

**Don't let it affect your learning.**

GMAT

GRE

1st Grade

2nd Grade

3rd Grade

4th Grade

5th Grade

6th Grade

7th grade math

8th grade math

9th grade math

10th grade math

11th grade math

12th grade math

Precalculus

Worksheets

Chapter wise Test

MCQ's

Math Dictionary

Graph Dictionary

Multiplicative tables

Math Teasers

NTSE

Chinese Numbers

CBSE Sample Papers