Final answer:
The average force exerted on a 2 kg cart that accelerates at 15 m/s² is calculated using the formula F = ma, resulting in an average force of 30 Newtons.
Step-by-step explanation:
The question involves calculating the average force exerted on a cart which accelerates at a certain rate. Using Newton's second law of motion, the formula F = ma (force equals mass times acceleration) can be applied. Given that the mass (m) of the 2 kg cart accelerates at 15 m/s2 for 3 seconds, the average force (F) that creates the change in speed can be calculated as follows:
F = ma = (2 kg) × (15 m/s2) = 30 N
Therefore, the average force that creates the change in speed is 30 Newtons.