/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 64 The length of an arc intercepted... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

The length of an arc intercepted by a central angle of \(\alpha\) radians in a circle of radius \(r\) is _______.

Short Answer

Expert verified
The arc length is \(r \alpha\).

Step by step solution

01

Understand the formula for arc length

To find the length of an arc intercepted by a central angle in a circle, use the formula: \ \[s = r \times \theta\] where \(s\) is the arc length, \(r\) is the radius of the circle, and \(\theta\) is the central angle in radians.
02

Substitute given values into the formula

In this problem, the central angle is given as \(\alpha\) radians and the radius is \(r\). We substitute these into the formula: \ \[s = r \times \alpha\]
03

Simplify the equation

After substitution, the arc length formula becomes: \ \[s = r \alpha\]

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Central Angle
A central angle is an angle whose vertex is at the center of a circle and whose sides are radii of the circle. It plays a crucial role in determining the arc length and can be measured in degrees or radians.
To visualize, imagine slicing a pizza: the angle at the center, where you start cutting, is the central angle.
Central angles are important in defining portions of the circle, or arcs. For instance, a central angle of 90 degrees will divide the circle into a quarter. Understanding this is key for solving problems involving arc length.
Radians
Radians offer a way to measure angles that relates directly to the circle's circumference. Unlike degrees, which divide a circle into 360 parts, radians define the angle based on the arc length relative to the radius.
Specifically, one radian is the angle created when the length of the arc equals the radius of the circle.
Since the circumference of a circle is \(2\tr \times \text{radius}\text{ ( } r \text{)}\text{, with } \) \frac{360 \text{ degrees equal to } 2 \tr}, a full circle in radians is 2 \tr. This link simplifies many calculations, especially in trigonometry and calculus.
Circle Radius
The radius of a circle is the straight-line distance from the circle's center to any point on its perimeter. This measurement is crucial in determining the length of an arc.
In geometric problems, the radius often serves as a given or an unknown quantity that you must solve for.
When you know the radius and the central angle, you can plug these values into the arc length formula. This makes the radius a key component in finding out important circle properties, including area, circumference, and arc length.
Trigonometry Formula
The arc length formula, \[s = r \times \theta \] \ \r represents the radius and \theta represents the central angle in radians, leverages key trigonometric principles.
This formula essentially states that the length of an arc is a proportion of the circle's circumference: the proportion is the same as that of the central angle to the full angle circle (2 \tr radians).
This makes trigonometric functions and formulas very practical in geometry problems involving circles. Knowing how to manipulate and apply this formula can help you solve a variety of problems concerning the properties of circles.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

A wheel is rotating at\(200 \mathrm{rev} / \mathrm{sec}\). Find the angular velocity in radians per minute (to the nearest tenth).

Eratosthenes Measures Earth Over 2200 years ago Eratosthenes read in the Alexandria library that at noon on June 21 a vertical stick in Syene cast no shadow. So on June 21 at noon Eratosthenes set out a vertical stick in Alexandria and found an angle of \(7^{\circ}\) in the position shown in the drawing. Eratosthenes reasoned that since the sun is so far away, sunlight must be arriving at Earth in parallel rays. With this assumption he concluded that Earth is round and the central angle in the drawing must also be \(7^{\circ} .\) He then paid a man to pace off the distance between Syene and Alexandria and found it to be \(800 \mathrm{~km}\). From these facts, calculate the circumference of Earth (to the nearest kilometer) as Eratosthenes did and compare his answer with the circumference calculated by using the currently accepted radius of \(6378 \mathrm{~km}\).

Solve each problem. Motion of a Spring A weight is suspended on a vertical spring as shown in the accompanying figure. The weight is set in motion and its position \(x\) on the vertical number line in the figure is given by the function $$ x=4 \sin (t)+3 \cos (t) $$ where \(t\) is time in seconds. a. Find the initial position of the weight (its position at times $$ t=0) $$ b. Find the exact position of the weight at time \(t=5 \pi / 4\) seconds.

A forest ranger atop a 3248-ft mesa is watching the progress of a forest fire spreading in her direction. In 5 min the angle of depression of the leading edge of the fire changed from \(11.34^{\circ}\) to \(13.51^{\circ} .\) At what speed in miles per hour is the fire spreading in the direction of the ranger? Round to the nearest tenth.

Use a calculator to find the value of each function. Round answers to four decimal places. $$ \sec \left(-9^{\circ} 4^{\prime} 7^{\prime \prime}\right) $$

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.