SOLUTION: By how much does the arc intercepted by a central angle of 38 degrees exceed the chord intercepted by the same angle on a circle of radius 43 ft.? Please help me :(

Algebra.Com
Question 1096676: By how much does the arc intercepted by a central angle of 38 degrees exceed the chord intercepted by the same angle on a circle of radius 43 ft.?

Please help me :(

Found 2 solutions by KMST, MathTherapy:
Answer by KMST(5328)   (Show Source): You can put this solution on YOUR website!
NOTE:
I assume this is math homework,
and not physics homework.
I also assume that the answer is expected to be a length in feet,
because if the expected answer was 1.9%,
There would be no need to know the radius.
In that case, you would compare the length of
a arc on a unit circle with
(the measure of the arc in radians)
to the sine of ,
to find that


A PICTURE AND THEN AN ANSWER IN 1,000 WORDS:


LENGTH OF THE ARC:
Using radians:
The angle measure is in radians.
The length of an arc of that measure is
angle in radians times radius.
For a circle of radius, it is .
Without radians:
The whole circumference is .
The arc is a fraction of that. It is .
So, the arc length is .
That is approximately .

LENGTH OF THE CHORD:
Connecting the ends of the chord to the center of the circle,
you form an isosceles triangle.
It has two legs measuring forming an angle measuring .
It's base is the chord, whose length we need to find
If Law of cosines was taught in class, you may be expected to use it.
.
So,
That is approximately .

Otherwise, you could split that triangle into two right triangles,
and use trigonometry to find the length of half the chord as
,
so the length of the chord is twice that,
or approximately .

By how much does the arc exceed the chord?
We calculate the difference as about ,
So, I would answer .

Answer by MathTherapy(10557)   (Show Source): You can put this solution on YOUR website!
By how much does the arc intercepted by a central angle of 38 degrees exceed the chord intercepted by the same angle on a circle of radius 43 ft.?

Please help me :(
Let central angle be O, radii AO and BO, and intercepted chord & intercepted arc, AB
∡A = 38o
Length of arc AB:
∡A and ∡B =
Draw an altitude from vertex O to AB, and name it C
cos ∡A =

--------- Cross-multiplying
AC = 14
Since the altitude from vertex O, or OC BISECTS chord AB, AC = . Therefore, the INTERCEPTED CHORD or
Arc AB exceeds chord AB by .
RELATED QUESTIONS

How long is an arc intercepted by the given central angle in a circle of radius 11.16 m?... (answered by solver91311)
The length of the arc intercepted by a central angle of 2 radians in a circle of radius... (answered by macston)
Find the length of the arc, S, on a circle of radius 7 feet intercepted by a central... (answered by lwsshak3)
please help!!?? find the length of the arc on a circle of radius r =50 inches... (answered by ankor@dixie-net.com)
Find the length of arc , S, on a circle of radius 3 meters intercepted by a central angle (answered by ankor@dixie-net.com)
A circl ewith a diameter of 20 cm has a centeral angle of 50 degrees. What is the length... (answered by Fombitz)
Find the arc length intercepted in a circle of radius 2.65 m by a central angle of 1.98... (answered by ikleyn)
Find the length of the arc on a circle of radius r intercepted by a central angle. Then... (answered by stanbon)
Find the length of the arc intercepted by a central angle of 65 degrees in a circle of... (answered by stanbon)