00:01
This question, we have to find the length of the arc of a circle with center angle 40 and the radius of 20.
00:05
That is part a.
00:07
So we know that there's a direct formula for to find the arc length.
00:13
And the central angle formed as theta.
00:15
And mind that theta should be in radiance.
00:17
And the arc length is s and the radius is r.
00:21
Then the formula says that theta in radiance is arc length over radius.
00:26
Now, theta is given us 40, but that is in degrees.
00:29
So we multiply by pi over 180 to convert in radiance.
00:34
The arc length is something which we have to find and the radius is 20 centimeters.
00:39
So all we have to do is cross multiply.
00:41
And let's give the answer in terms of pi only...