An arc can be measured either in degree or in unit length. An arc is a portion of the circumference of the circle which is determined by the size of its corresponding central angle. We create a proportion that compares the arc to the whole circle first in degree measure and then in unit length.
(measure of central angle/360 degrees) = (arc length/circumference)
arc length = (measure of central angle/360 degrees)(circumference)
But, maybe the angle that determines the arc in your problem is not a central angle. In such a case, find the arc measure in degree, and then write the proportion to find the arc length.
you will need to know the angle subtended by the arc; arc length = radius x angle in radians
You also need the measure of the central angle because arc length/2pi*r=measure of central angle/360.
I'm assuming that "c" is short for "circumference". The length of an arc is (circumference)*(360/angle). So the length of an arc in a circle with circumference length of 18.84 is 6782.4/angle, where the angle is measured in degrees.
To find the arc length given the radius and angle measure in degrees, you must first convert the angle from degrees to radians, using the formula: Degrees = Radians X (pi/180). Then take the radians and the radius that you are given, and put them into the formula of Q = (a/r) where Q is the angle in radians, a is the arc length, and r is the radius. When you have this, simple multiply both sides by the radius to isolate the a. Once you do this, you have your answer.
5.23
you will need to know the angle subtended by the arc; arc length = radius x angle in radians
(arc length / (radius * 2 * pi)) * 360 = angle
The answer will depend on what other information is given.
You also need the measure of the central angle because arc length/2pi*r=measure of central angle/360.
you need to know the formula the arc length is equal to the radius times the angle made by the length of arc s = r(theta) s=arc length r=radius theta=angle
With the information given, you cannot. You need the radius or the central angle.
Length = angle˚/360˚ x 2∏r
By using a protractor and finding the angle between the two radii
angle of arc/ angle of circle (360°) = length of the arc/ total circumference (2 pi* radius) so you just have to find r then so: angle of arc/ angle of circle (360°) *2pi = length of the arc/ radius radius= ength of the arc/ angle of arc/ angle of circle (360°) *2pi not that hard ;)
length of arc/length of circumference = angle at centre/360 Rearranging the equation gives: length of arc = (angle at centre*length of circumference)/360
Well, in degrees, the arc is congruent to its central angle. If the radius is given, however, just find the circumference of the circle (C=πd). Then, take the measure of the central angle, and divide that by 360 degrees. Multiply the circumference by the dividend, and you will get the arc length. This works because it is a proportion. Circumference:Arc length::Total degrees in triangle:Arc's central angle. Hope that helped. :D
You can use the cosine rule and the three lengths of the triangle to find the central angle X, (in radians). Then the length of the arc is r*X units.