The formula for calculating the center angle of a circle with known arc length and radius of a sector

The formula for calculating the center angle of a circle with known arc length and radius of a sector

If the arc length is l, the radius is r
Then the number of radians of the center angle of the circle α= l/r

The radius of the circle is 5cm, and the arc length opposite a central angle is 6.28cm______ Degrees

According to the formula of arc length, l = n π R
180 know,
The center angle of the sector is:
6.28÷3.14÷5 × 180，
=0.4 × 180，
=72 (degrees)
A: the central angle of this circle is 72 degrees
So the answer is: 72

If the length of an arc is a and the central angle of the circle opposite it is 120 °, then the radius of the circle where the arc is located is RT

Set the radius to R
From the arc length formula:
2π/3*R=A
The solution is r = 3A / 2 π

If the radius of the circle where an arc is located is 12cm and the center angle of the arc is 60 °, then the length of this arc is______ Centimeter

three point one four × two × twelve × （60°÷360°）
=6.28 × twelve × one
6，
=12.56 (CM),
A: the length of this arc is 12.56 cm
So the answer is: 12.56

If the center angle of an arc with an arc length of 6 π is 60 °, the radius of the circle where the arc is located is __

60πr
180=6π，
The solution is r = 18

Given the chord length and radius of an arc, calculate the length of the arc (expansion size) Chord length 19.95 radius 17 find the arc length

sin@=19.95/(17*2)
(2*17*3.14)*（2@/360.）
Students:
Calculate the answer yourself!