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Example Questions
Example Question #3 : Find The Length Of The Arc Of A Circle Using Radians
Find the length of an arc of a circle if the radius is and the angle is .
Write the formula for arc length.
Substitute the known radius and angle.
Example Question #5 : Find The Length Of The Arc Of A Circle Using Radians
When CERN was designing its Large Hadron Collider, they needed to run a cable from the control house to a spot radians around the circle. If the Large Hadron Colider has a radius of , what length of cable will be necessary to reach the sensor?
When CERN was designing its Large Hadron Collider, they needed to run a cable from the control house to a spot radians around the circle. If the Large Hadron Colider has a radius of , what length of cable will be necessary to reach the sensor?
The formula for length of an arc is as follows:
Thus, to find the measure of the central angle, what we are really doing is multiplying the total circumference by the fractional part of the circle we are interested in. In this case, we already have the radius and the central angle, we just need to plug and chug.
So our answer is:
Example Question #6 : Find The Length Of The Arc Of A Circle Using Radians
If a circle has a circumference of 310 kilometers, find the length of the arc associated with a central angle of radians.
If a circle has a circumference of 310 kilometers, find the length of the arc associated with a central angle of radians
Recall that arc length can be found via the following:
Upon closer examination, we see that the formula is really two parts. The first part gives us the fractional area of the circle we care about. The second part is simply the circumference. This means that if we multiply the whole circumference by the fraction that we care about, we will just get the arc length of the portion we care about.
So, plug it in and go!
Looks messy, but we'll simplify it.
So our answer is 116km.
Example Question #7 : Find The Length Of The Arc Of A Circle Using Radians
Find the arc length of a circle with circumference that goes from to around its center.
Remember that arc length of a circle is given by:
, where is angle made by connecting the radius to the two ends of the arc, given in radians. is the radius.
To get , we convert from degrees to radians.
To get the radius we convert from the circumference
Example Question #2 : Find The Length Of The Arc Of A Circle Using Radians
If the length of is and , which of the following is closest to the length of minor arc ?
The formula for arc length of a circle, given in radians, is , where is the arc length.
Then, plug in the givens: and simplify: .
Then round to the appropriate placement: .
Therefore, the arc length of is .
Example Question #1 : Find The Area Of A Sector Using Radians
Find the area of a sector if the radius of the circle is 4, and the angle of the sector is radians.
Write the formula for the area of the sector in radians.
Substitute the radius and theta.
Example Question #1 : Find The Area Of A Sector Using Radians
Find the area of a sector if the radius is 1 and the angle of sector is radians.
Write the formula for the area of the sector in radians and substitute the given values.
Example Question #1 : Find The Area Of A Sector Using Radians
If the diameter of a circle is 6, find the area of a sector with a sector angle of .
Write the formula for the area of the sector in radians.
The given diameter is 6, which means the radius is 3.
Substitute both the radius and theta to solve for the area.
Example Question #1 : Find The Area Of A Sector Using Radians
Find the area of a sector with the radius of 1 and angle of .
Write the formula for the area of a sector in radians.
Substitute the radius and the angle.
Example Question #1 : Find The Area Of A Sector Using Radians
Find the area of a sector with a radius and angle of . Express the answer in terms of .
Write the formula for the area of a sector. Substitute the radius and angle to solve for the area.
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