Car going up a hill. Find the Angle of the hill.

In summary: Going up, the engine produces 44 hp more power to sustain the constant velocity than it does going down the same hill. At what angle is the hill inclined above the horizontal? Going up a hill, the car's engine produces 44 hp more power to sustain the constant velocity than it does going down the same hill. The angle at which the hill is inclined above the horizontal is 45 degrees.
  • #36
Right. How do you now bring in the 44 hp?
 
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  • #37
Set the equations equal to each other and add 44 to the "up hill" side
 
  • #38
Do you want to add it to the "up hill" side or the "down hill" side? Also, is hp the SI unit for power?
 
  • #39
o right becasue going uphill is 44 more hp you would add it to the downhill side. and no 1hp=745watt
 
  • #40
Right. (1 hp = 746 W the last I checked, but who's counting?) [OK, just checked, it's 745.699872 W for 1 "mechanical hp" and exactly 746 W for "electrical hp". Trivia for the day.]

http://en.wikipedia.org/wiki/Horsepower
 
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  • #41
So just checking my equation:

v(f+mgSinθ)=v(f-mgSinθ) + 32810.8w

Now I can just plug and chug.
 
  • #42
Yep. Good work!
 
  • #43
I got a domain error... [never mind calculator error]
 
  • #44
What?
 
  • #45
I just put my nunmbers in my calculator wrong. No big deal thanks again.
 
  • #46
ok. No problem.
 
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