parabolic chart with excel 3

[sept2006]

Hello,
I am trying to plot these data. I am supposed to get a parabolic curve (upside down umbrella), but what I get is almost a straight line.

I guess it is because the time scale is too wide. is there a way i could narrow the x-scale on my graph?

(Is this really the only problem?)

Time Distance
0,033 0,0479
0,066 0,0587
0,099 0,0693
0,132 0,0799
0,165 0,0906
0,198 0,1013
0,231 0,1118
0,264 0,1225
0,297 0,1331

thanks a lot.

 

[SkipVought]

Hi,

play with the Value axis MinScale value. Narrow the MIN to MAX range.

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[GlennUK]

You are getting a straight line because the data IS a straight line.

You have time intervals of 0.033 with increases of:
0.0108
0.0106
0.0106
0.0107
0.0107
0.0105
0.0107
0.0106

Can see you see how straight that is?

Cheers, Glenn.

Did you hear about the literalist show-jumper? He broke his nose jumping against the clock.

 

[sept2006]

thanks Glen,

it is the distance that should be parabolic when plotted on the y-axis (and time as x-axis with equidistant intervalles)

 

[xlhelp]

Make your Y axis logarithmic and adjust the scale

Me transmitte sursum, Caledoni!

 

[SkipVought]

y = ax[sup]2[/sup] + bx + c

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[xlhelp]

I hadn't looked closely at your data. I knew the time lines were same interval, but your distance is also same interval. You need an exponential progression to get a parabolic curve. The log scale will generate a curve, but to what use?


Me transmitte sursum, Caledoni!

 

[sept2006]

you're right.
i think my data is not correct.
this is an oucome from a free fall experiment. the displacement should be a function of time squared.


thanks.

 

[SkipVought]

d = 1/2 gt[sup]2[/sup]

t = (2 d/g)^[sup].5[/sup]

g = -9.8 m/s


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