The Big Misconception   

So what's the big deal? Many people have known Newton's first law since eighth grade (or earlier). And if prompted with the first few words, most people could probably recite the law word for word. And what is so terribly difficult about remembering that F = ma? It seems to be a simple algebraic statement for solving story problems. The big deal however is not the ability to recite the first law nor to use the second law to solve problems; but rather the ability to understand their meaning and to believe their implications. While most people know what Newton's laws say, many people do not know what they mean (or simply do notbelieve what they mean).

Learning ≠ Storing

Cognitive scientists (scientists who study how people learn) have shown that physics students come into physics class with a set of beliefs that they are unwilling (or not easily willing) to discard despite evidence to the contrary. These beliefs about motion (known as misconceptions) hinder further learning. The task of overcoming misconceptions involves becoming aware of the misconceptions, considering alternative conceptions or explanations, making a personal evaluation of the two competing ideas and adopting a new conception that is more reasonable than the previously held-misconception. This process involves self-reflection (to ponder your own belief systems), critical thinking (to analyse the reasonableness of two competing ideas), and evaluation (to select the most reasonable and harmonious model that explains the world of motion). Self-reflection, critical thinking, and evaluation. While this process may seem terribly complicated, it is simply a matter of using your noodle (that's your brain).

The most common misconception is one that dates back for ages; it is the idea that sustaining motion requires a continued force. The misconception has already been discussed in a previous lesson, but will now be discussed in more detail. This misconception sticks out its ugly head in a number of different ways and at a number of different times. As your read through the following discussion, give careful attention to your own belief systems. View physics as a system of thinking about the world rather than information that can be dumped into your brain without evaluating its consistency with your own belief systems.

Newton's laws declare loudly that a net force (an unbalanced force) causes an acceleration; the acceleration is in the same direction as the net force. To test your own belief system, consider the following question and its answer as seen by clicking the button.