Question

An airplane starts at a stand-still and speeds up with an acceleration of 8.9 m/s². If the runway is 117 m long, how long will it take for the airplane to reach the end of the runway?

A) 5 seconds

B) 10 seconds

C) 13 seconds

D) 15 seconds

Answer 1

To determine how long an airplane takes to travel down a 117m runway at an acceleration of 8.9 m/s², we use the kinematic formula s = ½at². Solving for time, the calculation suggests it takes approximately 5 seconds for the airplane to reach the end of the runway.

Step-by-step explanation:

To calculate the time it takes for an airplane to reach the end of a 117m long runway with an acceleration of 8.9 m/s², we can use the kinematic equation s = ut + ½at² where s is the distance, u is the initial velocity, a is the acceleration, and t is the time. Since the airplane starts from rest, u is 0, making the equation s = ½at². Plugging in the numbers, we get 117m = ½(8.9m/s²)t², which simplifies to t² = (2 × 117) / 8.9.

Solving for t yields t ≈ 5 seconds, which is option A, the correct response.