Understanding the Concepts

* Acceleration: The rate at which an object's velocity changes over time.

* Initial Velocity: The velocity of the object at the start of acceleration. We'll assume the airplane starts from rest (initial velocity = 0 mph).

Calculations

1. Final Velocity: To find the final velocity, use the following formula:

* Final Velocity = Initial Velocity + (Acceleration * Time)

* Final Velocity = 0 mph + (20 mph/second * 30 seconds)

* Final Velocity = 600 mph

Answer: The airplane would be traveling at 600 mph after 30 seconds of acceleration.

Important Note: This calculation is a simplification. In reality, airplanes have a maximum speed limit, and their acceleration rate would likely decrease as they approach that limit.