All i have to do is plug this info into the sector area formula remembering to use a conversion factor in order to convert to radians, and simplify. The nonshaded area of the circle shown below is called a sector. See the video below for more information on how to convert radians and degrees. Area of a sector of circle formula with solved examples. Arc length area of a sector of a circle length of a circular arc. How to find the area of a sector of a circle a plus topper. Then, area of a sector of circle formula is calculated using the unitary method. Area formula for all shapes and calculator download pdf for students. For this exercise, theyve given me the radius and the arc length. Jan 21, 20 example problems on area of sector radians.
One ray is the initial side and the other is the terminal. R 2 we have seen in this section how we are supposed to calculate area and perimeter of circle and arc. Area enclosed by an arc of a circle or area of a sector. Exercise worksheet for area of a sector of a circle radians. The area of a sector is like a pizza slice you find the area of a circle times the fraction of the circle that you are finding. I remember this formula as it is quite easy to remember. The nonshaded area would still be a sector if the angle at the centre of the circle was larger, or smaller, than a rightangle 900. Radian, arc length, sector area learning made simple.
Area and arc length of a sector george brown college. As we know mathematics is not a spectator sport so we also got through its application in some practical examples of area and perimeter related to circle and arc. Prove that the area of a circular sector of radius. Vedantu explains more about the area and perimeter of a sector of a circle with examples. The following is what ive come up with so far, am i on the right track. The a grade student can already remember all the necessary formulae in the o level formula sheet though it is given anyway during exam to refer to. Converting degrees and radians, arc length, and sector area. Each sector has a unique central angle that it subtends at the center of the circle. Jan 07, 2014 arc length of a circle formula sector area, examples, radians, in terms of pi, trigonometry duration. Alevel maths edexcel c2 june 2008 q7b examsolutions.
Scroll down the page for more explanations, examples and worksheets for the area of sectors and segments. In this example the sector subtends a rightangle 900 at the centre of the circle. Exercise worksheet for area of a sector of a circle. If you are given degrees, round the answer to the nearest tenth of a degree. So in the below diagram, the shaded area is equal to.
A radian is the measure of the central angle of a sector of a circle with arc length of one radius length. The topics in this course includes probability and statistics, geometry and trigonometry, numbers and shapes, algebra, functions and calculus. It consists of a region bounded by two radii and an arc lying between the radii. Jan 31, 2016 we discuss what a sector is as well as the formula for finding the area of a sector with a central angle in radians. The area of a sector calculator is used to help you find the area of a sector of a circle. If we had carried out the calculation of arc ab to six significant digits, we would have obtained s 31. Let this region be a sector forming an angle of 360 at the centre o.
There is a lengthy reason, but the result is a slight modification of the sector formula. Exercise3 a sector of a circle is an area bounded by two radii and an arc. Select the input value you want, then enter their values. Given a sector with radius r 3 cm and a corresponding arc length of 5. The area of a segment is the area of a sector minus the triangular piece shown in light blue here. The formula is a little complicated to do in your head. Please input radius of the circle and the central angle in degrees, then click calculate area of sector button. The ratio of the area of the sector to the area of the full circle will be the same as the ratio of the angle.
Using the formula for the area of the sector, a 1 2. All i have to do is plug this info into the sectorarea formula remembering to use a conversion factor in order to convert to radians, and simplify. Finding an arc length when the angle is given in degrees. The triangle is equilateral so each of its angles has a degree measure of. Given a circle the area of sector is 3 s in 2 and the central angle is 6 s. So lets consider a sector of a circle of radius r and central angle. Understanding area of a sector formula is always challenging for me but thanks to all math help. A sector of a circle is a closed figure bounded by an arc of a circle and two of its radii. What is the approximate size of the playing area of the baseball eld. Formulae for arc length, sector area and segment area. So i can find the shadedgreen area by finding the area of one sector remembering to convert to radians, and multiplying the result by 2. We typically will draw angles in the coordinate plane with the. A particular baseball eld is a quarter of a circle, like the sector of the circle shown in the gure below, where angle is 90 and the radius is 100 yards. Use the sector area formula and the given information to find the sector area.
To find the area of the sector you can either use the formula for sector area or view the sector as some part of the total area of the circle. Exercise worksheet on find the area of a sector of a circle when the angle is given in radians. Therefore, we realize that the arc length of a sector is directly proportional to its central angle. The area of a sector of a circle with a central angle of 4 rad is 8 m2. Well email you at these times to remind you to study. Sector area calculator calculate area of a sector area. When applying the formula s r, the value of must be in radian. The following table gives the formulas for the area of sector and area of segment for angles in degrees or radians. I can tell that a circular sector looks similar to a triangle with an arc replacing its flat base. If you are given radians, write the answer in terms of s and use the button to round answers to the nearest tenth.
Area of a sector of a circle formula solved questions. Area of a sector and segment solutions, examples, worksheets. This page includes a lesson covering finding the area of a sector of a circle when the angle is given in radians as well as a 15question worksheet, which is printable, editable, and sendable. Arc length and area of a sector to find the length of arc ab, we convert to radians by multiplying by 180. When the angle at the center is 360, area of the sector, i. The following is the calculation formula for the area of a sector. To find the area of the sector, i need the measure of the central angle, which they did not give me. Area of a sector how to find formula radians youtube.
Find the length of the intercepted arc in each circle with he given central angle measure and radius. When applying the formula sr, the value of must be in radian. Derive using similarity the fact that the length of the arc intercepted by an angle is proportional to the radius, and define the radian measure of the angle as the constant of proportionality. The same applies for the area of the sector as well. Prove that the area of a circular sector of radius r with central angle theta is, where theta is measured in radians.
When the angle at the center is 1, area of the sector \\frac\pi. Whether you want to calculate the area a, arc s, or one of the other properties of a sector including radius r and the angle formed, then provide two values of input. If, instead of a central angle in degrees, you are given the radians, you use an even easier formula. A sector of a circle is the shape formed by slicing up a circular cake. Formulae for arc length, sector area and segment area a summary of the formulae for length of an arc, area of a sector and area of a segment. One ray is the initial side and the other is the terminal side. All i need to do is understand that theyve given me a radius being the value for everything within and an angle measure, and theyve asked me to find the area of the resulting sector.
Calculate the area of a sector of a circle calculator online. What the formulae are doing is taking the area of the whole circle, and then taking a fraction of that depending on what fraction of the circle the sector fills. If the two lines are formed at a 180 degree angle then the sector is often referred to as a semicircle. If the sector of the circle measures 180 degrees, what is that portion of the circle. Two rays that have a common endpoint vertex form an angle. Express the ratio of the area of the sector to the area of the full circle in radians. As you can easily see, it is quite similar to that of a circle, but modified to account for the fact that a sector is just a part of a circle. To figure the area of a sector simply use our sector area calculator. Both use the proportion of angle measures in order to derive the desired information.
203 74 782 118 38 1389 602 1299 1438 152 181 1016 374 1516 1176 643 552 1444 903 394 612 923 175 835 1446 1391 1145 719 122 1028 550 1489 756 1494 529 325 1307 656 354 134 885 670 606 1145