Posts Tagged ‘basics’
Very simply, parallax is an apparent motion of an object due to a change in observation position. Let me start with an example. Here are two photos. I took a picture of the cabinet in the background from two slightly different positions. In the foreground is a clone trooper that did [...]
It’s odd, I have used centripetal acceleration quite often, but I never derived the expression that I use. To get to the point, the magnitude of the acceleration of an object moving in a circle is:
Moment of inertia is different than mass, but I like to call it the “rotational mass”. What does mass do? Things with larger mass are more difficult to change their motion (translational motion). A similar thing is true for the “rotational mass”. Things with larger rotational mass are more difficult to change rotational motion. Here is the demo.
So, you are taking a college science course. Maybe it is physics, maybe it is chemistry, maybe its a lab. Either way, you always end up with these problems that involve unit conversions. You think you have the hang of it, but sometimes you make some mistakes. Here is my explanation for converting units.
Collisions aren’t really that complicated. Basically, two objects interact and both object change momentum. Since the forces are the same (via Newton’s third law), momentum is “conserved.
Pre Reqs: Work-Energy
You need to be familiar with work and energy to understand this. If you are not familiar, look at the pre requisite link. Ok? Now, let’s begin.
Suppose a ball moves from point A (3 m, 3 m) to B (1 m, 1 m) at a constant speed as shown in [...]
Pre Reqs: What is a Force
Previously, I talked about the momentum principle. Very useful and very fundamental idea. The other big (and useful) idea in introductory physics is the work-energy theorem. Really, with work-energy and momentum principle, you will be like a Jedi with a lightsaber and The Force – extremely powerful.
Well, [...]
Maybe you know I like numerical calculations, well I do. I think they are swell. VPython is my tool of choice. In the post Basics: Numerical Calculations I used vpython and excel to do something simple. I will do that again today (in that this problem could also be solved analytically). [...]
Pre Reqs: Kinematics, Momentum Principle
What are “numerical calculations”? Why are they in the “basics”? I will give you really brief answer and then a more detailed answer. Numerical calculations (also called many other things – like computational physics) takes a problem and breaks into a WHOLE bunch of smaller easier problems. [...]
Pre reqs: Free Body Diagrams, Force, Kinematics
The time has come to look at things that are NOT in equilibrium. The most basic question to ask yourself is: “What do forces do to an object”? Aristotle would say that forces make things move. Constant forces make things move constantly. Actually, Aristotle said [...]