What defines a class 2 rocket?

A class 2 rocket is defined by its specifications concerning total impulse and the type of propulsion system used. Specifically, it is characterized as a rocket that utilizes propulsion systems or motors that result in a total combined impulse of less than 40960 Newton-seconds. The significant aspect here is that it is classified as a rocket other than a model rocket, which distinguishes it from lower classifications that commonly involve model rocket engines.

The total impulse threshold is essential for categorizing rockets into their respective classes, and the distinction between model rockets and other types ensures clarity in regulations and safety standards. The categorization allows for a structured approach to rocketry, ensuring that rockets with different capabilities are properly identified and regulated for safety and performance.

In this context, the other options do not fully encapsulate the definition of a class 2 rocket, either by limiting the scope to model rocket engines or by not specifying the inclusion of other types of rockets with specific impulse limits. Therefore, defining a class 2 rocket in terms of motors with a total impulse of less than 40960 N-s—specifically accentuating that it is not a model rocket—accurately reflects the classification criteria used in rocketry standards.