A jet plane is cruising at 310 m/s when suddenly the pilot turns the engines up to full throttle. after traveling 4.0 km, the jet is moving with a speed of 400 m/s.

For this problem, we would be using the formula: Vf^2 = Vi^2 + 2ad

where:

Vf = 400m/s

Vi = 300m/s

a = ?

d = 4.0km

= 4000m

400^2 = 300^2 + 2a4000

a = [ 160000 - 90000 ] / 8000

a = 8.75m/s^2

rounding it off to 2 significant figures, will give us 8.8 m/s^2.