Bob watches a flag being raised. He is 80 feet away from the bottom of the flag pole when the flag is on the ground, about to rise, and the angle of elevation is changing at a rate of 5 degrees per second.
How fast is the distance between the ground and the flag changing when the flag is 6 feet off the ground?
2006-10-31 12:05:36 · 1 answers · asked by GreaterFire 1 in Science & Mathematics ➔ Mathematics
Well, when the flag is just starting up and the angle of elevation is changing at a rate of 5 deg/s, that is equal to (5 pi / 180) radians/s.
And one radian is equal to 80 feet, so the flag is rising above the ground at (5 pi / 180) (80) ft/s.
Now, how fast is the distance from the ground changing when the flag is 6 feet off the ground? I don't know. Is it being raised at a constant rate? If so, see the answer at the end of the preceding paragraph. If not, the problem doesn't provide enough information to calculate an answer. (Basically, it gives you the speed at time 1 and asks you to find the speed at time 2, without telling how the two are related.)
2006-10-31 12:31:43 · answer #1 · answered by actuator 5 · 0⤊ 0⤋