Recent content by Stealth849

hm, if i integrate surface area from 0 ro the Radius, that would give me volume.. so if I take the integral of ρ*dA from 0 to R where dA = 4*pi*r^2*dr ?

Can you elaborate a little bit? I'm not too sure what I should be integrating here... ρ should be in C/m3 To get Q from ρ, I need to cancel the volume... I don't see what to integrate to achieve this though. Thanks

Net electric field is found form the electric field created by the charges. Electric field is also a vector quantity which can be summed. E = kq/r2 You should be able to find the electric field for each charge and through vector addition, find the net field. Also consider: The...

Homework Statement A spherical insulator of radius R and charge density ρ = ρo/r2 where r is the distance from its centre. Find the electric field at a point inside and outside the insulator. Homework Equations EA = Qencl/εo The Attempt at a Solution What's throwing me off is...

Within the shell, it is zero, but there would still be charge on the surface of the shell, which would be within the gaussian cylinder.

Ah, I see... In this case, the x cancels were left with E = λ/2∏r For any r in the defined region. Then for a region r > R2 How would I deal with finding Qencl with two charge densities? Also, wouldn't I need to know the charge density of the shell in m3 as the shell has...

So really what we get for part a is: E = Qencl/εo where Qencl = λx where x is any distance on the infinite line? So E = λx/εo? One thing though, would the field created by the cylindrical shell change the field, even though we are only looking at enclosed charge to get the...

Because the field lines must be perpendicular to the gaussian surface at all times, yes? I realize the axis must go through the center line of charge so that the surface of the cylinder will actually fulfill that requirement. But I don't know how to choose the necessary radii from the axis outwards.

Hm, Thanks for the reply. Sorry I am very lost for this... could I simply say that the radius of the gaussian cylinder is R1 - r, for the first region? I guess to clarify, I don't know if the edge of the gaussian cylinder can be anywhere within that region. For the region, r > R2, the...

Homework Statement A long line of charge with density λ (C/m) is surrounded by a concentric cylindrical conducting shell of inner radius R1 and an outer radius of R2. The shell carries a net charge of -2λ (C/m). Use Gauss' Law to determine the electric field as a function of the distance 'r'...

Homework Statement A continuous sinusoidal longitudinal wave is sent along a coil spring from a vibrating source attached to it. The frequency of the source is 25vib/sec, and the distance between successive rarefactions in the spring is 24cm. a) Find the wave speed b) if the max...

Well, if we replace the y0sin[k(vt-10)] portion of the F = ma equation, that would give F = -mk2v2y This somewhat models Hooke's law, if we can consider m, k, and v to be all constants and serve as the constant in the Hooke's law equation. Is this more on the right track..?

I'm sure it still is... Looking forward to learning it eventually when college rolls around. :) Do you mind giving me a quick introduction to how that equation works...?

Ah, thought you were referring to the k's in the derived equation. Sorry! Anyway, if F = ma = -kx Would x in this case be y? and thus y0sin[k(vt-10)] so ultimately we see -mk2v2y0*sin[k(vt-x)] = -Ky0sin[k(vt-x)] where uppercase K is spring constant, the amplitudes cancel, the...

Is the chain rule not just multiplying the initial derivative by the derivative of what is in the brackets of the sin function? where k(vt-10) is a product rule? if k is a constant, derivative is zero, derivative of (vt - 10) should be v (which I forgot to put in... argh) So equations...