H=v/(2pir)
You just have to isolate h. To do that you are going to divide both sides by 2pir.
Answer:
640 m
Step-by-step explanation:
We can consider 4 seconds to be 1 time unit. Then 8 more seconds is 2 more time units, for a total of 3 time units.
The distance is proportional to the square of the number of time units. After 1 time unit, the distance is 1² × 80 m. Then after 3 time units, the distance will be 3² × 80 m = 720 m.
In the additional 2 time units (8 seconds), the ball dropped an additional
... (720 -80) m = 640 m
_____
<em>Alternate solution</em>
You can write the equation for the proportionality and find the constant that goes into it. If we use seconds (not 4-second intervals) as the time unit, then we can say ...
... d = kt²
Filling in the information related to the first 4 seconds, we have ...
... 80 = k(4)²
... 80/16 = k = 5
Then the distance equation becomes ...
... d = 5t²
After 12 seconds (the first 4 plus the next 8), the distance will be ...
... d = 5×12² = 5×144 = 720 . . . meters
That is, the ball dropped an additional 720 -80 = 640 meters in the 12 -4 = 8 seconds after the first data point.
The units are the complete story on this question. All of the choices are over 1 so the units make the answer over one. It takes more feet than it does inches to make the scale. The correct units are 120 feet / 3 inches. That makes A and B both incorrect.
You can't get 360 by any method but multiplication. The units for multiplication would be ft*in. So D is wrong. That only leaves you with C which is the answer.
9514 1404 393
Answer:
34.6 ft
Step-by-step explanation:
The distance can be found using the Pythagorean theorem. Where a, b, c are the sides of a right triangle with c as the hypotenuse, it tells you ...
a² + b² = c²
a = √(c² -b²)
base-to-string = √(39² -18²) = √1197 ≈ 34.598
The distance from the base of the pole to the end of the string is about 34.6 feet.