Understanding Arc Length and Radians

The video tutorial explains how to find the length of a green arc intercepted by an angle at the center of a circle. The angle is given in radians, and the radius of the circle is known. The tutorial describes the concept of radians and how they relate to arc length, leading to the calculation of the arc's length using the formula: arc length = angle in radians × radius. The final result is derived by multiplying the angle in radians by the radius, resulting in the arc length in units.

What is the center of the green arc in the problem?

• Q

• A

• B

• P

What is the measure of angle P in radians?

• 0.2 radians

• 0.6 radians

• 0.4 radians

• 0.8 radians

What is the length of the radius given in the problem?

• 6 units

• 5 units

• 4 units

• 3 units

What does the angle in radians intercept in the circle?

• A line

• A square

• A point

• A green arc

How is the length of the arc related to the angle in radians?

• It is equal to the angle

• It is unrelated

• It is twice the angle

• It is half the angle

If an angle is 0.4 radians, how many radii long is the arc it intercepts?

• 0.4 radii

• 0.6 radii

• 0.2 radii

• 0.8 radii

What is the proper term for the plural of radius?

• Radiuses

• Radials

• Radii

• Radius

How do you convert the arc length from radii to units?

• Divide by 5

• Multiply by 5

• Add 5

• Multiply by 2

What is the final length of the green arc in units?

• 4 units

• 2 units

• 1 unit

• 3 units

What is a key takeaway about radians and arc length?

• Arc length in units is the angle in radians times the radius

• Arc length is always half the angle

• Arc length is always twice the angle

• Radians are unrelated to arc length