Power of a Jet Engine: 1.5 * 10^9 Nm/s

AI Thread Summary
A jet engine produces 1 * 10^5 N of thrust while moving an airplane at 900 km/h. The correct conversion of 900 km/h to meters per second is 250 m/s, not 15000 m/s. Using the power formula P = Fv, the power developed by the engine is calculated as P = (1 * 10^5 N)(250 m/s), resulting in 250,000 W or 25 MW. The initial miscalculation stemmed from an incorrect speed conversion. The discussion highlights the importance of accurate unit conversions in physics calculations.
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A jet engine develops 1 * 10^5 n of thrust in moving the airplane forward at a speed of 900 km/h. What is the power developed by the engine?

I thought I needed to convert 900 km/h to m/s, so I did and I got 15000 m/s.


The only equation I see to use for this is:

P = Fvcosθ


When I used the equation, I got:

P = Fv
= (1*105)(15000 m/s)
= 1.5 * 109


I know I went wrong somewhere because it is multiple choice and that wasn't any of the answers. Please help me see my error(s) and help me get it right. I need this done a.s.a.p. by tomorrow. Thanks.
 
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900 km/h to m/s, so I did and I got 15000 m/s.

How many seconds are there in one hour?
 
900km/hr= 900000m/s divide by 3600 sec/hr and you get what?
Edit: sorry rootx, missed your response.
 
My mistake. I completely missed that.

900000 m/h /3600 s = 250 m/s

And then I multiply that by the thing I had before:

P = Fv
= (1 * 105 N)(250 m/s)
= 250000 W
= 25 MW

Thanks guys. I got too much going on in my mind right now. :redface:
 
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