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A construction company wants to build an arc-shaped curve with a radius of 30m. The center angle of the arc-shaped curve is 120 °, then the length of the curve is? (π takes 3)
First, find the total circumference length: C = 2 π r = 180m
Find 120 ° again, accounting for 1 / 3 of the whole circle
Then the curve length is 180 * 1 / 3 = 60m
A curve is an arc with a length of 12 π M. the center angle of the arc is 81 degrees. Find the radius of this curve (accurate to 0.5)
Radius of curve R: perimeter: arc length = 360 °: 80 °, (2) × R × ∏):12=360°:80°,R=(360°÷80°) × 12÷(2 × ∏)=4.5 × 12÷(2 × 3.14) = 8.598 ≈ 8.6 (m) (accurate to 0.1M)
The center angle of an arc whose arc length is equal to the radius is Online, etc
The answer upstairs is correct. The center angle is 1 radian and the angle value is 180 / π. I don't know whether you are in junior high school or senior high school. After senior high school, you are more used to using radians to represent the size of the angle
The arc length formula is L= θ* R = n π R / 180 (when n = 360 °, the formula is the circumference formula of the circle)
L is the arc length, and the center angle corresponding to the arc length is θ (in radians) n (in angles) when l = R θ= 1 n=180/π
There is a curve in the shape of an arc with a total length of 18.84 meters. The center angle of the arc is 90 °. What is the area of the circle where the arc length is changed?
Radius r = 18.84 ÷ (3.14) × 90 ÷ 180) = 12m
Area of circle with arc length = 3.14 × twelve × 12 = 452.16m ²
Given that the chord length of the center angle of 2 radians is 2, then the arc length of the center angle is () A. 2 B. sin2 C. 2 sin1 D. 2sin1
Connecting the center of the circle and the midpoint of the string, a right triangle is formed by the chord center distance, half the chord length and the radius. The half chord length is 1 and the center angle of the opposite circle is also 1
Therefore, the radius is 1
sin1
The arc length opposite the center angle is 2 × one
sin1=2
sin1
So choose C
Given that the chord length of the center angle of 2 radians is 2, then the arc length of the center angle is () A. 2 B. sin2 C. 2 sin1 D. 2sin1
Connecting the center of the circle and the midpoint of the string, a right triangle is formed by the chord center distance, half the chord length and the radius. The half chord length is 1 and the center angle of the opposite circle is also 1
Therefore, the radius is 1
sin1
The arc length opposite the center angle is 2 × one
sin1=2
sin1
So choose C
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