Final answer:
To find the mass of the crate on a frictionless incline with a known force and acceleration, use Newton's second law. The mass is calculated as 40 N divided by 2.0 m/s^2, resulting in 20 kg.
Step-by-step explanation:
To determine the mass of the crate on an incline, you can use Newton's second law of motion, which is F = ma, where F is the force, m is the mass, and a is the acceleration. In this case, we know the force applied up the incline (40 N), the acceleration of the crate (2.0 m/s2), and we need to determine the mass m. The equation can be rearranged to solve for mass by dividing both sides by acceleration, resulting in m = F/a. Thus, dividing the force by the acceleration, you get m = 40 N / 2.0 m/s2 = 20 kg. So, the mass of the crate is 20 kilograms.