Posted by Dakota on Tuesday, March 15, 2011 at 11:10pm.
A 747 jetliner lands and begins to slow to a stop as it moves along the runway. If its mass is 3.50x^5 kg. Its speed is 27.0 m/s, and the net braking force is 4.30x10^5 N. (a)what is its speed 7.50 s later? (b)how far has it traveled in this time?

physics  drwls, Wednesday, March 16, 2011 at 2:14am
Use the braking force and F = ma to get the deceleration rate, a.
(a) After t= 7.5 seconds, the velocity will be
V(7.5) = Vo  a t
= 27.0 m/s  a*7.5
(b) Distance travelled at t = 7.5s
= (Average velocity)* time
= (1/2)*(Vo + V(7.5)) * 7.5s 
physics  ChingChongWong, Thursday, June 2, 2011 at 9:33am
The answer is found with your teacher. Go ask your teacher