A plane accelerates from 0 kt to 180 kt in 9 s at constant acceleration. What is its acceleration in kt/s?

To determine the acceleration of the plane in knots per second (kt/s), you can use the formula for acceleration, which is defined as the change in velocity divided by the time taken to make that change.

In this scenario, the plane starts from an initial velocity of 0 knots and reaches a final velocity of 180 knots over a time period of 9 seconds.

First, calculate the change in velocity:

Final velocity - Initial velocity = 180 kt - 0 kt = 180 kt.

Next, divide the change in velocity by the time taken, which is 9 seconds:

Acceleration = Change in velocity / Time = 180 kt / 9 s = 20 kt/s.

Thus, the acceleration of the plane is 20 kt/s, aligning with the choice provided. This result demonstrates the relationship between a steady increase in speed over a defined time period.