CONCEPT PREVIEW Fill in the blank to correctly complete each sentence. One minute, written 1' , is ________________ of a degree.
Table of contents
- 0. Review of College Algebra4h 45m
- 1. Measuring Angles40m
- 2. Trigonometric Functions on Right Triangles2h 5m
- 3. Unit Circle1h 19m
- 4. Graphing Trigonometric Functions1h 19m
- 5. Inverse Trigonometric Functions and Basic Trigonometric Equations1h 41m
- 6. Trigonometric Identities and More Equations2h 34m
- 7. Non-Right Triangles1h 38m
- 8. Vectors2h 25m
- 9. Polar Equations2h 5m
- 10. Parametric Equations1h 6m
- 11. Graphing Complex Numbers1h 7m
1. Measuring Angles
Angles in Standard Position
Problem 37
Textbook Question
Find the measure of the smaller angle formed by the hands of a clock at the following times. 8:20
Verified step by step guidance1
Understand that the problem asks for the smaller angle between the hour and minute hands of a clock at 8:20.
Calculate the position of the minute hand: since each minute corresponds to 6 degrees (360 degrees / 60 minutes), multiply the number of minutes by 6. So, the minute hand angle is \(20 \times 6\) degrees.
Calculate the position of the hour hand: each hour corresponds to 30 degrees (360 degrees / 12 hours), and the hour hand also moves as the minutes pass. So, the hour hand angle is \(8 \times 30 + \frac{20}{60} \times 30\) degrees.
Find the difference between the two angles calculated: \(| \text{hour hand angle} - \text{minute hand angle} |\).
Since the clock is circular, the smaller angle between the hands is the minimum of the difference and \$360$ degrees minus the difference. So, calculate \(\min(\text{difference}, 360 - \text{difference})\).
Verified video answer for a similar problem:This video solution was recommended by our tutors as helpful for the problem above
Video duration:
4mPlay a video:
0 Comments
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Angle Calculation of Clock Hands
The angle between clock hands is found by calculating the positions of the hour and minute hands relative to 12 o'clock. Each minute, the minute hand moves 6 degrees, while the hour hand moves 0.5 degrees. Understanding these rates helps determine the exact angle at any given time.
Recommended video:
Drawing Angles in Standard Position
Converting Time to Angles
To find the angle at a specific time, convert the hour and minute values into degrees. The minute hand’s angle is 6 times the minutes, and the hour hand’s angle is 30 times the hour plus 0.5 times the minutes. This conversion is essential for precise angle measurement.
Recommended video:
Convert Points from Polar to Rectangular
Determining the Smaller Angle
Since the hands form two angles that sum to 360 degrees, the smaller angle is the minimum of the calculated angle and its supplement (360 degrees minus the angle). This ensures the answer reflects the smaller angle between the hands.
Recommended video:
Coterminal Angles
Related Videos
Related Practice
Textbook Question
579
views
