Question
A fighter jet is launched from an aircraft carrier with the aid of its own engines and a steam-powered catapult. The thrust of its engines is 2.6 times 105 N. In being launched from rest it moves through a distance of 87 m and has a kinetic energy of 4.4 times 107 J at lift-off. What is the work done on the jet by the catapult? A 0.700-kg particle has a speed of 1.50 m/s at and kinetic energy of 7.90 J at . What is its kinetic energy at What is its speed at What is the net work done on the particle by external forces as it moves from to
Explanation / Answer
a) KE at A = .5*.7*1.5^2 = .2*4 =0.7875 J
b) Speed at B = v
0.5*0.7 v^2 = 7.9J
v^2 = 22.57
v = 4.75 m/s at B
c) Work = 7.9 - 0.7875 = 7.1125 J from A to B