Is this some kind of homework?
I feel like
very often, but that is too much for me!
It is a shame I don't have
the book here. The thrust-power conversion was clearly explained.
I think you are calculating the power
developed by the airplane in a take off. It is OK that you are trying to compare with a Ferrari to have an idea of the magnitude. However I think that it makes no sense.
Any body being pushed by a force and moving is developing power, or "has" power. That power is directly proportional to the force applied and the speed, exclusively.
If at take off (about 150 kt ground speed with 60,000 pounds of thrust) an airplane develops a given power, how much power has the same airplane in cruise, flying at 500 kt groundspeed? Well, we need to know cruise thrust, I don't know, maybe 40,000 pounds?. Much more HP!
A Ferrari has to burn fuel to produce the power within the engine and then transfer it to its propulsive system (the wheels). The Ferrari cannot obtain more power than that (no wind, no slope). Twice as much fuel flow gives it twice as much power. And it has to "share" it between speed and thrust.
The 747 burns the fuel to get thrust in its propulsive system directly. Twice as much fuel flow, twice as much thrust. There is no limit to the power the airplane can reach, other than the limits to its speed and thrust. If it keeps accelerating for a constant thrust, its power will keep increasing.
Imagine a car with a 1000 hp engine. At full throttle, brakes on, it "has" no HP yet (zero speed) but it has, say, 1000 pounds of push force. After releasing brakes and having accelerated to its maximum speed (when the thrust is equal to drag plus friction) it has the 1000 HP the engine can provide it, but no longer 1000 pounds of thust. It has less, because now it has speed. The propulsive system has less and less ability to produce thrust with the horsepower from the engine as it speeds up until the thrust cannot overcome the opposing force and speed becomes constant. It could never get more than 1000 Hp even in case there were no opposing forces at all.
The same car with a 1000 pounds jet engine (trying to have a page in the Guinnes Book) also reduces somewhat its thrust with speed, but due to other factors. Thrust becomes less an less but power will increase with speed as long as speed increases. However if there are compressibility effects (high mach number) thrust will start increasing with speed! Then we would have high airspeeds and high thrust as well. That means the car would "have" more and more power.
Simply put, jet engines are thrust producing machines, they don't give us power for fuel. You cannot compare them.
Maybe you can compare fuel burnt during the take off roll of a jet airplane with that burnt by a car running the same distance. If they use different fuels, you need to find the energy released by burning a kilo of each. That would be comparing the energy required to cover that distance.
If you then find their kinetic energies you can calculate and compare the efficiency of the engines, too. You could also find the same for a whole flight/trip from A ot B, and find what is more fuel efficient per each 1,000 kg transported ¿By air or by car? ¿What contaminates more, 200 people going to the beach 400 miles away in their cars or in a 737?
haha That is homework! And of course I am no physics teacher so I cab be radically wrong!
I just felt very very