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Ch. 3 - Radian Measure and The Unit Circle
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161, 9780135440780, 9780136881117, 9780135440827, 9780135924891당신이 사용하는 게 아니라요?교과서 변경
4장, 문제 41

Distance Traveled by a Minute Hand Suppose the tip of the minute hand of a clock is 3 in. from the center of the clock. For each duration, determine the distance traveled by the tip of the minute hand. Leave answers as multiples of π . 30 min

검증된 단계별 안내
1
Identify the radius of the circular path traveled by the tip of the minute hand. Since the tip is 3 inches from the center, the radius \(r\) is 3 inches.
Recall that the distance traveled by a point moving along a circular path is the length of the arc it covers. The formula for arc length \(s\) is \(s = r \theta\), where \(\theta\) is the central angle in radians.
Determine the fraction of the full circle the minute hand moves in 30 minutes. Since the minute hand completes one full rotation (360 degrees or \(2\pi\) radians) in 60 minutes, in 30 minutes it moves half the circle, so \(\theta = \pi\) radians.
Calculate the arc length using the formula \(s = r \theta\). Substitute \(r = 3\) inches and \(\theta = \pi\) radians to express the distance traveled as a multiple of \(\pi\).
Write the final expression for the distance traveled by the tip of the minute hand in 30 minutes as \(3\pi\) inches, leaving the answer in terms of \(\pi\) as requested.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
3m

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Arc Length Formula

The arc length of a circle segment is calculated by multiplying the radius by the central angle in radians. It is given by the formula s = rθ, where s is the arc length, r is the radius, and θ is the angle in radians. This formula helps find the distance traveled along the circular path.
추천 영상:
가이드 코스
4:18
Finding Missing Side Lengths

Conversion Between Degrees and Radians

Angles can be measured in degrees or radians, where 360° equals 2π radians. To use the arc length formula, convert degrees to radians using the relation radians = (π/180) × degrees. This conversion is essential for applying trigonometric formulas correctly.
추천 영상:
가이드 코스
5:04
Converting between Degrees & Radians

Minute Hand Movement and Angular Displacement

The minute hand completes a full 360° rotation every 60 minutes, so its angular speed is 6° per minute. For a given time, the angular displacement is found by multiplying the time by this rate. Understanding this helps determine the angle subtended by the minute hand's movement.
추천 영상:
가이드 코스
5:08
Sine, Cosine, & Tangent of 30°, 45°, & 60°