Question

An aircraft, initially stationary on a runway, takes off with a speed of 85 km h¹ in a distance of no

more than 1.20 km.
What is the minimum constant acceleration necessary for the aircraft?
A 0.23ms-²
B 0.46ms ²
C 3.0ms ²
D 6.0m

Answer 1

A. 0.23 ms⁻²

Step-by-step explanation:

Using the equation:

v² = u² + 2as

where:

v = final velocity (85 kmh⁻¹ = 85 x 0.278 = 23.6 ms⁻¹)

u = initial velocity (0 ms⁻¹)

a = acceleration (? ms⁻²)

s = displacement (1.20 km = 1.2 x 1000 = 1200 m),

`(23.6)^2 = (0)^2 + 2 (a) (1200)`

⇒
`a = (23.6^2)/(2(1200))`

⇒ a = 0.23 ms⁻²