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1. I Integrating FFT, python code

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) =...
2. I Integrating FFT, python code

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...
3. I Extracting sinusoids from FFT

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

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...
5. I Extracting sinusoids from FFT

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...
6. Max force help

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...
7. Help with basic physics problem.

MOST EXCELLENT! Thank you all so much for your time and patients:P
8. Help with basic physics problem.

i thought i had to convert it to N/m much like you have to convert 57g to .057kg right?
9. Help with basic physics problem.

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?
10. Help with basic physics problem.

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?
11. Help with basic physics problem.

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...
12. Help with basic physics problem.

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...
13. Help with basic physics problem.

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)
14. Help with basic physics problem.

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...
15. Help with basic physics problem.

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...
16. Help with basic physics problem.

so i should have my work converted to lbs/ft? can i ask you just off the top of your head what would be a probable estimate of what lbs/ft spring i would need? ok so lets just say 20 lbs/in converted = 240 lbs/ft (1/2)mv2 = (1/2)kx2 .5(.057)9.9^2=240x^2 2.793/240=x so x=.011? however this...
17. Help with basic physics problem.

This isn't like a normal home work problem. It's like one of those that your teacher gives at the end of the week that is super hard for some extra credit. All I was told was that "If someone has a spring cannon that could shoot 10 m at a 45 degree angle what type of spring would need to be in...
18. Einestein favourite physicist?

omg! i totally get springs now! lol -sarcasm- js i like this forums sense of humor :)
19. Help with basic physics problem.

so should Vi=9.9 then? (if sin(45) = 1) ok how could i do that then? Like what formula would I need to use? Could i use ma=-kx?
20. Einestein favourite physicist?

i understand this. i didn't ask the original question. but still doesn't help me understand springs :(
21. Einestein favourite physicist?

j/w why is it tht a 100 people will post abt a crazy topic but no one will help me with my homework :(
22. Einestein favourite physicist?

to many smiles to be non-conspicuous....
23. Einestein favourite physicist?

lonely people do lonely things...
24. Help with basic physics problem.

1. Homework Statement If a tennis ball with a mass of 57 g is shot out of a spring cannon at a 45 degree angle and goes 10m find the answer to the following questions: What is the velocity. What spring constant must the cannon have. What would be the constant converted into lbs/in. 2...
25. Einestein favourite physicist?

maybe it's not a question as to who was Einsteins favorite whatever, but why?
26. Einestein favourite physicist?

now now lets be rational we want the truth! then again what is the truth? can we prove that anything is true?
27. Einestein favourite physicist?

yes those rolling stones were quite the bomb of physics back then.
28. Help me with springs.

Isn't the k measured in N/m though? So if a 20 pound/in spring would have 2.257 N/m. would this be the same as the k? k=2.257?
29. Einestein favourite physicist?

w8 stien-I invented the g-4 bomb didn't he!? or did he cut down tht cherry tree?
30. Einestein favourite physicist?

Idk, some dude that invented relativity or something? :P