Beginning of IB Physics SL :)

So far our class has been just reviewing concepts from freshman year, nothing all that new yet. We've covered position, distance, displacement, speed, and velocity. We've mentioned velocity here and there, but really haven't delved into it as much as the other topics mentioned. So i'll just go over a quick run down of things.

So to the left you're looking at a very basic position vs time graph. The topic of comparing position, distance, and displacement came up. So in this example, At 5 seconds:
Position: 50 m
Distance: 50 m
Displacement: 50 m
All of these came out to be the same in this scenario, BUT THIS IS NOT ALWAYS THE CASE!!!!!

So before I dive in deeper, I think it's a good idea to define the terms I've used so far.

Position- Position is the location the object is at. So in the graph above, at 5 seconds the position is at 50m.
Displacement- Displacement is how far the object is relative to the reference point. Direction matters!
Distance- Distance is the amount traveled in total regardless of direction.

So here's a question: What's a scenario where position, displacement, and distance are all different? 

So basically here's an answer. Obviously this isn't the only answer but the general idea applies. Basically to answer this, your starting point and reference point need to differ and at one point you need at least one positive and negative slope on your graph.

So in this graph specifically, the intervals on the y-axis go up by 20, and the x intervals increase by 1. 

I will evaluate the graph at 6 seconds.

Position: 20 m

Displacement: 0 m

Distance: 80 m

Also, since we already have a graph above, we might as well knock two birds out at once and talk about velocity and speed as well.

Velocity: displacement/time

Speed: distance/time

So for the example above

Average velocity: 0/6 = 0 m/s/s

Average speed: 80/6 = 13.3 m/s

Just to tie in acceleration a little, basically the slope of a position vs time graph equals velocity, and then the from the slope of a velocity graph you can get acceleration. 

 The topic of linearizing came up, which confused some. And i'll admit, last year in chemistry we were just handed a worksheet and we were told to linearize without really any discussion on it and I was just lost. But with a little research I knew what it actually meant, and the concept is fairly simple.

 
So basically, this is what helped me the most. If it's still confusing after this, I recommend watching youtube videos that can clearly explain it in a few minutes with examples and whatnot.

We also did a lab which was pretty fun. So basically we were given a boiling flask that was 500 ml, which looked like this:

So basically we measured, and in our flask only the bottom circular portion was 500 ml, and the neck was 50 ml. So our task was to basically record the height at a certain amount of time. So what we did was we did a scale that 1 sec = 1 ml. And since there was 550 ml, theoretically, 25 ml with 22 trials should fill up the entire flask. So basically, we would put in 25 ml of water, which would also represent 25 seconds, and then we would measure the height of the water with the ruler. We ended up having to do 24 cups of 25 ml, due to imprecise measuring (we literally used like 8 different beakers and graduated cylinders because of the time crunch) but this was pretty insignificant because it did not effect what were analyzing. Basically, when the flask is thinner the slope of the position vs time graph would be steeper, and then at the wider parts it would be less steep. What was really cool about this experiment, was that if you turned the flask sideways that's what the velocity vs time graph would look like. I just thought that was really cool and worth sharing about.