Download 1 Name: Math In Trades Unit 6 – Triangle Trigonometry REVIEW ҉

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Name: _____________________________
Math In Trades
Unit 6 – Triangle Trigonometry REVIEW
҉ DMS DD (Converting between Decimal Degrees & Degrees,
Minutes, Seconds)
Examples: Convert from decimal degrees to the nearest second.
1) 47 3/8º
2) 36 ¾º
3) 73 3/5º
4) 16.11º
3) 57º36’
4) 168º54’
Examples: Round to the nearest thousandth of a degree
1) 1º12’
2) 96º9’
↔ Converting Between Degrees & Radians
π radians = 180 degrees
Examples: Convert all angle measures to radians. Round to three significant digits.
1) 10º45’
2) 35.26º
3) 90º
Examples: Convert to degrees and round to the nearest hundredth.
1) 0.05 rad
2) 4.3 rad
3) 1.43 rad
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∆ SOH CAH TOA
sinA = opposite
hypotenuse
cosA = adjacent
hypotenuse
tanA = opposite
adjacent
Examples: Find the missing part of the triangle.
1)
2)
3)
4)
5)
Find m <U
6)
Find m <K
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↖→↙↓ Linear & Angular Speed (a = angle in radians)
Linear Speed: v = d
t
Angular Speed: w = a
t
Examples:
1. If a car travels 1800 ft in 24 seconds, what is its average linear speed for the trip?
2. If a 24-in.-diameter flywheel rotates through an angle of 140º in 1.1 seconds, what is the average
angular speed of the flywheel?
3. A belt-driven drum of radius 28.4 cm makes one revolution every 0.250 sec. What is the linear speed
of the belt driving the drum? Round to three significant digits. (Hint: If the belt doesn’t slip, the
distance traveled by the belt in one revolution is equal to the circumference of the drum)
4. The blade on a shop fan rotates at 8.0 rev/sec. Calculate its average angular speed. Round to two
significant digits. (Hint: each revolution is 360º)
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⃝ Sectors (REMEMBER: a = angle IN RADIANS)
Examples:
1. A sheet metal worker wants to know the arc length and area of a sector with central angle 150º cut
from a circular sheet of metal with radius 16.0 in.
2. Calculate the arc length and area of a sector with central angle 80º and radius 25.0 ft. Round to three
significant digits.