Newton’s Second Law of motion as it applies to Space Rails
As we have established with the first of law, an object cannot be set into motion without the application of a force. The second law further establishes the relationship between the force applied on an object and the object’s motion. Newton’s second law of motion looks even more difficult to memorize. But, you should remember it’s not important to memorize these concepts. Once you are able to have a full appreciation of the principles and applications of the law, writing it down would come naturally.
The Second Law
‘The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.’
There is a simple equation that summarizes this law.
Where "F" represents the magnitude of the force, "m" represents the mass of the object, and "a" represents the acceleration.
To break this down, if you push two toy cars with the same mass down a smooth road, the toy car you gave the heavier push would move faster. In this illustration, the push is the force applied and how fast the car moves gives an idea of the acceleration. And of course, it is assumed that the mass is constant.
To further understand this concept, think about why a small car would usually find it easy to overtake a big truck on an express road. It’s because of the differences in their mass. Even if both drivers are applying the same force on the accelerator (although there is much more to a car’s motion that this), the smaller car would move faster because of its lesser mass. It’s the same reason why you are able to push the lawnmower in your garden but you are not able to push the car, even if you apply the same force.
Although you may not be able to quantify your observation, you could notice the relationship between force and acceleration on a space rail. As explained in the first law, the motion of the marble on the space rail depends on gravity. The gravitational pull on this marble is greater at the very sloppy points on the rail. Thus, the force exerted on the marble at these very sloppy points is higher than the force exerted at the less sloppy points. According to the second law, the acceleration of the marble should be greater at the very sloppy points. This is exactly what you would observe on the space rails. The marble moves much faster at the points where the slope is steep and then slows down at points where the rail is almost straight. In fact, the changing speeds of the marble till it gets to the end point is in response to the changing magnitude of the gravitational pull that’s driving its motion.