The radius of the circle where an arc is located is 60 cm, and the angle of the center of the circle where the arc is located is 80 degrees. What fraction of the circumference of the circle is occupied by this arc? Write the process and the answer, to speed oh

The radius of the circle where an arc is located is 60 cm, and the angle of the center of the circle where the arc is located is 80 degrees. What fraction of the circumference of the circle is occupied by this arc? Write the process and the answer, to speed oh

The center angle of an arc is 80 ° and the arc occupies the circumference of its circle
80÷360
=8/36
=2/9
two-ninths

The arc length corresponding to the center angle of 72 ° is the circumference of the circle

72/360=1/5

In a circle of radius 1, what fraction of the circumference of the circle is the length of the arc opposite to the center angle of 30 degrees

30 △ 360 = 1 / 12

Given that the center angle of the sector is 150 degrees, then the arc length of the sector is the circumference of the circle

∵ sector arc length L = α r = 150 π R / 180 circle circumference C = 2 π R
The ratio of the two is: L / C = 5 / 12
Answer: the arc length of the sector is 5 / 12 of the circumference of the circle

The length of an arc is one ninth of the circumference of the same circle, and the angle of the center of the arc is ()

The length of an arc is one ninth of the circumference of the same circle, and the angle to the center of the arc is (40 degrees)
A circle is 360 degrees, so 1 / 9 is 40 degrees

1. If the central angle of the circle is reduced to one ninth of its original value, and the radius of the circle is reduced to one third of the original value, is the original arc length enlarged or reduced? How much is the original arc length? 2. In a circle with a radius of 1cm, what is the central angle of an arc whose arc length is two thirds of that of cm?

After a day, I don't know if it's useful for you. I just saw the problem and finished it as soon as possible
1, the original arc length must be reduced; it is the original: (1 / 9) * (1 / 3) = 1 / 27;
2. The center angle of an arc whose arc length is two-thirds of CM = (2 π / 3) / 1 = 2 π / 3 (radian),
=（2π/3）*180°/π=120°；
I hope it can help you

Why are the two arcs of equal length_____ Not necessarily_____ It's an equal arc

The curvature of the arc may be different, that is, it may not be on the same circle

Are two arcs of equal length equal? Why

no
The length and shape of equal arc fingers are equal
Two arcs of equal length in the same circle or equal circle are equal arcs

Is it true that an arc of equal length is an equal arc? An arc of equal length is an equal arc Is that right? Why?

incorrect
"Equal arc" is a very imprecise concept. When we say "equal arc", we should clearly point out whether the degree is equal, the length is equal, or whether the degree and length are equal
In plane geometry, it is stipulated that "in the same circle or equal circle, the arc that can completely coincide is called equal arc". The definition of equal arc indicates that arc of equal degree or arc of equal length are not necessarily equal arc, only the arc of equal degree and length can be called equal arc

If two arcs of equal length are equal arcs, why not

Not necessarily. The radian may be different