One of the constant reminders I tell my students is that "reality is always more complex than the textbook problem." And our goal is to dig into things and events that we all take for granted every day, and try to find the complexities in the seemingly simple. Here's one example of what we mean by this:
You have a superball, hold it some height above the floor, and then drop it. That's it, seems incredibly simple! And we all have done this, and know what happens. It hits the floor, and bounces back up to nearly the same height from which we dropped it.
What's the key word in this description???? What indicates within our observation that this is trickier than we tend to think????
"Nearly." The best superball in the world cannot make it back to its original height. The world's best pendulum or swing or roller coaster can never make it back to their original heights. The scientist's question is, of course, why is this the case with everything we can think of that starts high, goes down and tries to return to the same height?
When the superball falls, it is moving through air. There is air friction acting on it, and that interaction, that rubbing and collisions with air molecules, creates heat, which means there is a loss in kinetic energy. The ball then collides with the ground. ANY material in a collision get partially deformed during the collision. The two surfaces produce forces on each other and bend/deform/compress each other. The atoms and molecules in the two surfaces have their bonds disturbed, and are vibrating faster in their lattice positions...basically a shock wave goes through the materials. This is all internal heat and movements of atoms and molecules...it is taking more kinetic energy away from the ball during its journey. We hear the superball hit the ground - sound energy is produced during collisions, and that is a small loss of energy from the ball. It starts moving back up, through air, and more heat is released due to air friction.
All of this complexity, usually at small distances where the atoms and molecules themselves are being affected drastically, all requires energy of the system, and it is impossible for any object to bounce back to its original height.
If you can start to think about reality differently than the general conceptual approach of most textbooks, then you are thinking like the scientist. And this opens the door to all sorts of research questions, as we can then investigate how significant a specific parameter or effect has on a system! This is the CABS approach, and is why we can always find good, original research questions in everyday things, and don't always need the million dollar laboratory to do real, good research!!
HAPPY 2021!!! Let the exploring and curiosity begin!!!!
