# Thread: Motor HP Quiz Question

1. Wrongo.....

[Edited by condenseddave on 02-15-2005 at 01:36 AM]

2. That one made sense for a minute, now I'm second-guessing that 40% thing. Please stand by.........

This was the smartest thing I posted on this thread.

[Edited by condenseddave on 02-15-2005 at 01:37 AM]

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Aren’t you supposed to be on vacation?

I say it's D for down shifting. LOL

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(RPM1/RPM2) = (CFM1/CFM2)

(BHP1/BHP2) = (RPM1/RPM2)^3

8000CFM/1000CFM = 0.8 = (RPM1/RPM2)

0.8^3 =0.512 ==> approx 50% ish.

D.

5. 10x(8000/10000)3{Cubed}

Should be "8" as in 8 hp.

So, it's 20%

Pumps are easier.

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Well I’ll be…..look here, I was right.

7. Originally posted by clydemule
(RPM1/RPM2) = (CFM1/CFM2)

(BHP1/BHP2) = (RPM1/RPM2)^3

8000CFM/1000CFM = 0.8 = (RPM1/RPM2)

0.8^3 =0.512 ==> approx 50% ish.

D.
OK, that works.....

Aren’t you supposed to be on vacation?

Only from replying to nonsense threads and posts started by idiots that serve no real purpose. And that will only last until BC1 quits borrowing Don's balls to stop the trouble that they start, and then hightail it out.

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I agree.

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The motor is still 10hp.

11. ct2
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condenseddave

12. new H.P.=old H.P.(new CFM/old CFM)^3
=10(8,000/10,000)^3
=10(.8)^3
=10(.512)
new H.P.=5.12H.P., so answer is "D"

13. I have to agree with those who posted D.

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