If the length of a string is equal to the radius, then the radians of the central angle of the chord are? Why?

If the length of a string is equal to the radius, then the radians of the central angle of the chord are? Why?

60°
String is equal to radius. Isn't the triangle formed by chord and two radii an equilateral triangle? 60 degrees, of course

A chord of length equal to radius has an angle equal to the center of the circle______ Radian

Because a chord whose length is equal to its radius has a central angle of π
3 radians
So the answer is: π
3．

Is the length of a string equal to the radius, and the angle of the center of the circle that the string is facing is equal to 1 radian? Why?

Not equal to
A chord and its radii form an equilateral triangle with a center angle of 60 degrees and π / 3 radians

Given that the radius of circle O is 5cm, the chord AB = 5 root sign 2, find the degree of the angle AOB of the center of the circle to which the chord is directed

∠AOB=90°

In the circle O with radius r, if chord AB = R, chord AC = radical 3R, then ∠ BAC=

Connect OA, ob, OC
Then ∠ Bao = 60
In triangle ACO, the cosine theorem is used to solve ∠ OAC
R^2=R^2+3R^2-2*3^0.5R^2cos∠OAC
Cos ∠ OAC = 3 ^ 0.5/2, so ∠ OAC = 30
∠BAC=∠BAO+∠OAC=60+30=90
In the other case, C is on the B side, ∠ BAC = ∠ Bao - ∠ OAC = 30

In the circle O with radius 1, the lengths of chord AB and AC are root 3 and root 2 respectively. Find the degree of ∠ BAC The picture also needs, the process also needs

① The two strings are on either side of the center of the circle,
According to the vertical diameter theorem, ad = √ 3 / 2, AE = √ 2 / 2,
According to the value of trigonometric function in right triangle, we can know that:
sin∠AOD=√3／2,
∴∠AOD=60°,sin∠AOE=√2／2,
∴∠AOE=45°,∴∠BAC=75°；
② When two strings are on the same side of the center of the circle, they are 15 degrees
So BAC = 75 ° or 15 °
I'm sorry

A chord with a length equal to twice the root of the radius has an angle at the center of the circle

Because a chord is twice the root of the radius
Let radius = 1
Chord length = root 2
be
Two radius chords form an isosceles right triangle
therefore
Center angle = 90 degrees

In the circle O, if the length of the arc AB is 3 π and the angle of the center of the circle is 120 °, then the length of the chord AB is

3 π = 180 parts n π R
3 = 2R in 3
r=4.5

As shown in the figure, there is a length of 2 in ⊙ o with radius of 2cm If the chord AB is 3cm, the degree of the center angle of the circle to which the string AB is opposite is () A. 60° B. 90° C. 120° D. 150°

As shown in the figure, make OD ⊥ ab. according to the vertical diameter theorem, point D is the midpoint of ab,
AD=1
2AB=
3，
∵cosA=AD
OA=
Three
2，
∴∠A=30°，
∴∠AOD=1
2AOB=60°，
∴∠AOB=120°．
Therefore, C

In a circle of radius 2, the chord length is equal to 2 The chord center distance of 3 is___ .

Make a vertical line from the center of the circle to the chord, and get the chord center distance according to the Pythagorean theorem=
4-3=1．