Calculating Jet Engine Thrust and Power | Rocket Thrust Question

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SUMMARY

The discussion focuses on calculating the thrust and power of a jet engine based on specific parameters: an aircraft speed of 246 m/s, an air intake rate of 77.0 kg/s, and a fuel burn rate of 4.00 kg/s, with exhaust gases ejected at 633 m/s. The user correctly identifies that the change in momentum relates to impulse, using a 1-second time frame to calculate initial and final momentum. The initial momentum is calculated as 19926 kg*m/s, while the final momentum is -31347 kg*m/s, leading to a change in momentum that can be used to determine average force and, subsequently, thrust.

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Homework Statement


A jet aircraft is traveling at 246 m/s in horizontal flight. The engine takes in air at a rate of 77.0 kg/s and burns fuel at a rate of 4.00 kg/s. If the exhaust gases are ejected at 633 m/s relative to the aircraft, find the thrust of the jet engine and the delivered power.

find thrust and power

ive tried everything! even my teacher couldn't get the problem. but i refuse to just accept that i can't get it..please help would be greatly appreciated!
 
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If you've tried everything maybe you could show at least some of it.
 
ahh yes, sorry about that.

here's what i know. i know that it change in momentum is obviously is impulse. So i have it set to a 1 second time frame, and i found:

initial momentum = ((77 kg + 4 kg) * 246 m/s) = 19926 kg*m/s
TOTAL MASS * VELOCITY = Momentum

final momentum = ((77 kg + 4 kg) * -387 m/s) = -31347 kg*m/s
TOTAL MASS * VELOCITY = Momentum

the change in that would become the average force because impulse (which is change in momentum) is equal to average force * time. and the time is set to 1 in this instance.

anybody see flaws in the thinking?
 

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