Final answer:
The bike's acceleration will be faster than the train's acceleration due to its smaller mass for the same force applied.
Step-by-step explanation:
In physics, force is equal to mass multiplied by acceleration (F = ma). In this case, the force acting on both the train and the bike is 15N. However, the bike has a MUCH smaller mass than the train. According to Newton's second law of motion, a smaller mass will result in a greater acceleration for the same force applied. Hence, the bike's acceleration will be faster than the train's acceleration.