Question

You are watching a television show about Navy pilots. The narrator says that when a Navy jet takes off, it accelerates because the engines are at full throttle and because there is a catapult that propels the jet forward. You begin to wonder how much force is supplied by the catapult. You look on the Web and find that the flight deck of an aircraft carrier is about 90.0 m long, that an F-14 has a mass of 22300 kg, that each of the two engines supplies 27000 lb of thrust, and that the takeoff speed of such a plane is about 169 mi/h. Estimate the average force on the jet due to the catapult.
Please answer in kN

Answer 1

Answer:

653 kN

Explanation:

First get everything into metric units :

  169 miles/hr = 75.55 m/s

F = ma  

find the acceleration    from 0 to 75.55 m/s

  average is 75.55 / 2 = 37.775 m/s  

     so 90 meters takes   90 / 37.775 = 2.38 seconds

  vf = vo + at      

 75.55 = 0 + a * 2.38    shows a = 31.71 m/s^2

Now   F = ma

          F = 22300 (31.71) = 707133.3 Newtons

               subtract the engine force....the remainder is the catapult force

                      707033.3  - (27000 *2) = 653133.3 N  = 653 kN