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#1 2007-08-25 02:15:39
- Mel
- Guest
Geometric Progression
A spring is compressed and then released. The platform travels 50m up, 40m down, 32m up and so on
Determine the distance travelled in the 5th bounce
The answer is ~15m
#2 2007-08-25 04:16:57
- mathsyperson
- Moderator
- Registered: 2005-06-22
- Posts: 4,900
Re: Geometric Progression
Divide the second term by the first to find how much each term differs by the previous one.
40/50 = 0.8, so to get the (n+1)th term you would multiply the nth term by 0.8.
The third bounce is 32m, so the fourth bounce would be 32*0.8 = 25.6m.
Similarly, the 5th bounce is 25.6*0.8 = 20.48m.
Why did the vector cross the road?
It wanted to be normal.
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