Recent content by jameslat

Hi Mark, So the goal of this function is to accept the FFT of a discrete set of data points which represent an acceleration signal a(t) and find the position over time x(t). The input is fft(a(t))=a(w). I know that for ever harmonic in a(w), that the corresponding time domain signal is An(t) =...

Hello, Thank you for taking time to read my post. I have a discrete set of data points that represent an acceleration signal. I want to take the integral of this set of points twice so as to get a function which represents the position over time. To accomplish this, I have taken the FFT of the...

will iFFT( FFT('O') * FFT(H) ), result in a backwards 9? I haven't ever find anything like that before. It seems interesting though.

Works perfectly! I can't believe that it was that straight forward. You have been very helpful. Here is my python code as a contribution to the community (this is obviously for a dummy signal): import numpy as n import matplotlib.pyplot as plt from scipy.fftpack import fft, ifft, fftfreq...

Hello, Thank you for taking time to read my post. Background: I have a accelerometer project that I am playing with that gives me the acceleration of the object. I can plot this data and it looks very nice. I want to integrate this to get the velocity and then integrate it again to get the...

Hello, I built a small potato cannon out of PVC pipe/steel. It's 15.5 cm long, and about 7.6 cm wide on the inside. It's made of 2 parts the barrel and combustion chamber (or as i refer to, "the death chamber"). the "death chamber" is cylinder about 7.6 cm long and 7.6 cm thick. and the...

MOST EXCELLENT! Thank you all so much for your time and patients:P

i thought i had to convert it to N/m much like you have to convert 57g to .057kg right?

ok so tell me if i do this right if i have a spring that has 1 lbs/in which equals 175.12 N/m and if I put that into this equation. (1/2)mv2 = (1/2)kx2 .5(.057)9.9^2=.5(175.12)x^2 then that x=.1786 which is roughly 7.03 inches. Is this all correct?

so if i have a 20 lbs/in spring that is one foot long i need to push it 1 foot back to get my 20 pounds of force?

what if i shaved my tennis balls (don't laugh) and lubed the pipe with a silicon based oil? (like they use for cleaning gun barrels, like waxing it) that would minimize friction wouldn't it? and yes it is getting just a bit. so pulling it back 12 inches gives a .285 lbs. So if a spring says...

http://www.boltscience.com/pages/convert.htm why is it when I try and input my work with this calculator (above) I get a huge error (like 300 lbs/in)?also would this be right then? (1/2)mv2 = (1/2)kx2 .5(.057)9.9^2 = 25x^2 x=.3342 so I would only need to pull it back .334 of a meter with a...

ok 50 N/m = 442.53 lbs/in (and vice versa) @cupid.callin so with (1/2)mv2 = (1/2)kx2 and mass=.057kg V=9.9 m/s k=50 I'd be write to do the equation and get (1/2).057*9.9^2 = (1/2)50x^2 x=.334 Would this be accurate? Thanks again (things are starting to get clearer)

ok the fact is I'm trying to build one of these at home and I want to find out what type of spring to buy. and my math didn't make any sense when it said 247 pound/in spring so i was hoping to find the right answer with you guys. But i guess to my dilemma no one can help me unless if I have...

So your saying 9.9 m/sec is wrong to begin with? Just a reminder I'm a HS student and my teacher just got done teaching us basic 2-d kinematics and now is moving into springs and forces and half the equations that r being presented to me I never even seen before in my life. "Physicists seldom...