The working equation for this problem is a derived equation from the rectilinear motion at constant acceleration. The equation is written below:
2ax = v² - v₀²
where
a is the acceleration
x is the distance
v is the final velocity
v₀ is the initial velocity
Of course, the plane starts from rest, so v₀ = 0. The final velocity is the liftoff speed which is v = 120 km/h. Substituting the values:
2a(270 m) = (120 km/h)² - 0²
Solving for a,
a = 26.67 km/h²
