FCK!!!! Brain lock on physics question

[OSTIE]

Workin on some physics hw for the past couple hours and my brain is ready to take a sh.it.....

A nonconductor has an internal electric field that varies radially
E = 5.2 * (V/m^4) * r^3 * (r_vector)

a) Find the E force on an electron at r = .25m

b) Find the change in C from r = 0 to r = .24

c) The electron is released from rest at r = .25m, Find the speed of the electron at r = 0

[OSTIE]

Oh yea, let me say thanks in advance..... Im not even lookin for free-bies here, even a couple hints would probably help

[Psychotron]

magnetic fields? am i to assume this is a spehere? is that all there is to the detail of the question?

[OSTIE]

Yup thats why I am stumped, doesnt show a picture at all either

[AandF6969]

whats V? I'm assuming m is distance in meters?

And where the F is C in there? lol

[decadbal]

yea, um bump

[OSTIE]

V=voltage

[AandF6969]

Are you supposed to find it in terms of V cuz i think youve got too many unknowns in one equation... you dont know E and you dont know V

[OSTIE]

Are you supposed to find it in terms of V cuz i think youve got too many unknowns in one equation... you dont know E and you dont know V

This is why im stumped.... I dont know m either.

I think this is supposed to represent something like an extension cord, or power cord, etc... where m is the length of the extension cord, r is the radius, V is the voltage going through cord, etc. That is all I can think of. Im not sure how to manipulate this formula though to find out E for the first part. I emailed the teacher, hopefully he gets back to me letting me know he forgot to add another part to the question.

[arthurb999]

E=mc^2

[Powrlftr]

Buy the sol'ns manual you cheap bastard

[OSTIE]

Buy the sol'ns manual you cheap bastard

LOL, he made it up along with a crapload of others and gave us his own little worksheet.... its not due for a grade, but im **** sure positive ill see somethin like this on an exam.

[OSTIE]

If i knew there was going to be this much physics involved in getting a BA in engineering I woulda went into MIS or something, lol.

[Powrlftr]

If i knew there was going to be this much physics involved in getting a BA in engineering I woulda went into MIS or something, lol.

LoL, I hope you are joking about thinking engineering wasn't mostly physics. You should've done what I did to avoid the physics, become a synthetic organic chemist. The toughest math I do is simple arithmetic.

[AandF6969]

Now that i think about it m is usually mass... not meters or length

[1badcamaro]

Now that i think about it m is usually mass... not meters or length

and you made it to college??? WELL i've seen some of the ppl that have come out of your high school so i guess it shouldn't suprise me

[AandF6969]

and you made it to college??? WELL i've seen some of the ppl that have come out of your high school so i guess it shouldn't suprise me

Hey some of us are learning to be engineers trying to get real jobs, not get paid to sit around and eat donuts all day!

[bermich]

Ask Todd over at ANABOLICMONSTERZ.com He can answer anything.

[OSTIE]

A nonconductor has an internal electric field that varies radially
E = 5.2 * (V/m^4) * r^3 * (r_vector)

a) Find the E force on an electron at r = .25m

b) Find the change in C from r = 0 to r = .24

c) The electron is released from rest at r = .25m, Find the speed of the electron at r = 0

Just incase anyone was dying to figure this out, lol....
It ended up being easy as FCK and I didnt get it till i tried to put the r in the equation.... since r is in meters, the bottom of the equation is m^3... cancel that with the m^4 on top and you are left with E in terms of V/m... plug that value into the equation F(e_field) = qE and theres the answer to part A. The rest is all easy after that.

[arthurb999]

told you...

all about the mc^2

[ColdSore]

good god..what ever happened to addition and subtraction???