How to plot this stupid thing into excel...

**STLRamsFan** · May 27th, 2012 10:54 PM

Having technical trouble with this... Have this written on paper and such but cannot get this stupid thing to look correctly in excel, always ends up looking retarded, yet on paper it looks fine. My professor stupidly wants me to turn it in online so any idea how to get this thing to look right in excel? Used to be able to do this but haven't used excel in years...

Using Excel make a plot of the Position vs Time² given in the following table. The dependent variable is the position (y-axis) and the independent variable is the time (x-axis). This is the measured position of a rock as it falls from the top of a very high cliff and obeys the equations y = 1/2gt². Make sure you label the plot properly. Label the plot and the plot axes with the appropriate labels.

Measurement	Time (s)	Position (m)
1	0	0
2	1	5
3	2	21
4	3	46
5	4	82
6	5	129
7	6	185
8	7	252
9	8	330
10	9	417

Right click on a data point on the graph and add a “Trend line” Select a polynomial of order 2. This is a parabolic equation and describes an object falling under constant acceleration. Also show the equation on the graph. Since the acceleration of gravity is 2 times the coefficient of the x2 term, what you find for the acceleration of gravity. Copy and paste your graph into this document.

**Rentafence** · May 28th, 2012 12:16 AM

Like this?

**Timo** · May 28th, 2012 12:22 AM

Select all the data and plot using the scatter graph with only markers. Right click you data and select add trendline, then choose polynomial to the 2nd power.

e: while selecting your trendline click display equation on chart too add the equation.

**STLRamsFan** · May 28th, 2012 12:51 AM

Sweet, so far so good. Only thing I need to do is get the plot points to show their data (got the trendline equation no problem). How did you get the plot point data to show on the graph? Been years since I've actually used this thing so forgive me haha.

**STLRamsFan** · May 28th, 2012 12:56 AM

Well don't I feel like a frecking idiot. Just figured that out as well... Guess being so used to a different problem kind of complicates things a *tiny* bit haha. Appreciate the help guys! *+rep in spirit*

**Timo** · May 28th, 2012 12:59 AM

Click on a data point on the graph once to select all the data points, then right click and hit add data points. You can also get them by choosing one of the default designs, or in the layout tab under data labels (if you're using 2010, might be in '07 too). If you're using either '07 or '10, stuff like this is usually just a click or two away. I think you need to fart around in the menus for a couple of minutes to figure out how to do something in excel next time, will be much faster than asking here and will mean it'll be harder to forget.

e:derp

**STLRamsFan** · May 28th, 2012 01:31 AM

Last major thing, nothing excel related thankfully.

Calculate g using your equation

Coefficient of the x² Term = ____________________ “g” = ___________________

So with the y= 5.1591x^2 - 0.0864x + 0.0545 equation I got, I wrote the coefficient was 5.1591. Solving for "g" is where I'm stuck at...

First year doing physics is so much fun...

**Rentafence** · May 28th, 2012 02:05 AM

The derivative of position is velocity, and the derivative of velocity is acceleration. Since you have a position function, take the second derivative to get the equation for your velocity.

First Derivative - Velocity Function
y = 10.318x - .0864

Second Derivative - Acceleration Function (Constant in this case because there is no variable x)
y = 10.318

Therefore, the acceleration according to your data is 10.318m/s^2.