Calculating Height of Prop Tip at 12 Minutes: 2 of 2-Trig

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The height of the prop tip at 12 minutes is calculated using the formula h=11.5+8.5sin(800t). At t=12 minutes, the calculation involves converting the angle to radians, resulting in sin(9600) which equals approximately -0.8660. This leads to a height of 4.14 feet when substituting back into the equation. The initial incorrect height of 7.3 feet was due to a miscalculation. Therefore, the correct height of the prop tip is 4.14 feet above the ground.
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2 of 2--Trig

Kahleela starts the engine on her small airplane. The engine drives a prop with a radius of 8.5 feet and its centerline 11.5 feet above the ground. At idel, the prop rotates at a constant speed of @ 800 revs/minute. The height of one prop tip as a function of time is given by:
h=11.5+8.5sin(800t), where h is the height in feet and t is the time in minutes. When t= 12 minutes, what is h?

I came up with 7.3 feet...I was wrong...

Where did I stray?
 
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Radians and degrees? What is the answer?
 
Last edited:
a. 4.1 ft
b. 18.9 ft
c. 7.3 ft
d. 15.7 ft
 
12*800= 9600. Assuming that is in degrees, which seems most likely, sin(9600)= -0.8660. 8.5sin(9600)= -7.36 (is that where you got the "7.3"? Did you forget the last part?) 11.5+ 8.5sin(9600)= 4.14. The tip of the propellor is 4.14 feet off the ground.
 
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