An airplane that is flying level needs to accelerate from a speed of 2.00 × 10² m/s to a speed of
2) 40 × 10² m/s while it flies a distance of 1.20 km. What must be the acceleration of the plane?

Question

Quizplus · Accepted Answer

We can use the kinematic equation:

$v_f^2 = v_i^2 + 2ad$

where:

$v_f =$ final velocity = $2400$ m/s 
$v_i =$ initial velocity = $2000$ m/s 
$d =$ distance = $1200$ m

Solving for $a$:

$a = \frac{v_f^2 - v_i^2}{2d} = \frac{(2400	ext{ m/s})^2 - (2000	ext{ m/s})^2}{2(1200	ext{ m})} = 7.33 	ext{ m/s}^2$

Therefore, the acceleration of the plane is 7.33 m/s². The answer is (C).

An Airplane That Is Flying Level Needs to Accelerate from a Speed