Final answer:
The airplane's average speed during takeoff can be calculated as the arithmetic mean of the initial speed (0 m/s) and the final speed (54.8 m/s), which equals 27.4 m/s. (Option A is the correct answer)
Step-by-step explanation:
The average speed of an airplane during takeoff. Given that the airplane starts from rest and reaches a speed of 54.8 m/s, we can assume that the acceleration was constant over the takeoff period. The average speed under constant acceleration can be found by taking the arithmetic mean of the initial and final speeds.
In this case, the initial speed is 0 m/s (since it starts from rest), and the final speed is 54.8 m/s. Therefore, the average speed during takeoff is the mean of these two values.
Average Speed = (Initial Speed + Final Speed) / 2
Average Speed = (0 m/s + 54.8 m/s) / 2
Average Speed = 54.8 m/s / 2
Average Speed = 27.4 m/s
Thus, the correct answer to the student's question of what the plane's average speed during takeoff is would be Option A) 27.4 m/s.