/sci/ - Science & Math

>mfw no axes

>mfw no units

>mfw error bars

>mfw no axes

>mfw no units

>mfw no error bars

Find equation of best fit, take a derivative?

>finding the slope
>of a function with clear parabolic shape

you fucked up.

Spline interpolation please

>>2106321


>mfw no green text

You don't. That's obviously not a line. Either your hypothesis, your experiment, or your data analysis is screwed up somewhere. Find out which.

Your slope is looking to be something like -ax + C, right now.

I don't understand though. In the experiment we had a motion detector, and basically the person would stand in front of it, wait 2 seconds, walk 5 steps away from the motion detector then walk back and stand there until the 15 seconds are up.

>>2106359
Okay, so you are being asked to plot the person's velocity? Take <span class="math">v(t+\Delta t/2) \approx \frac{x(t+\Delta t) - x(t)}{\Delta t}[/spoiler].

I don't think what you are asking for is the slope, in the sense that it will be a single number or value, like for a straight line.

What you are asking for is the derivative. For your case of discrete points, it will simply be the slope between two adjacent point. So for your first two points, the slope is zero since the two points are parallel. As your friend starts moving the slope becomes positive, and when he walks back negative etc.

Just treat the slope you're asking for as the slope between the two adjacent points as I said.

What does this give physically? Well since what you show is a plot of position versus time, the slope between each point will give the velocity.

We can verify this by looking at the units. The units of slope will be [distance moved from one point to the next] divided by the [time to move that distance]. We see that distance divided by time is velocity as stated.

I really think when you ask for slope you mean the derivative. Plotting these slopes between adjacent point will give a plot of velocity versus time. I think this is what you're looking for.