Homework Help Group

[GodKnowsBest]

Hey besides E=V/d do you know any other ways to express electric field? I'm stuck on this one derivation and I can't simply use V=IR for Voltage because the Voltage can't be expressed in terms of resistance.

 

[GodKnowsBest]

My final exam is on tuesday

How did the final go abaayo macaan?

 

[Mokillem]

I

• I'm thinking of starting up a homework help group on here. I am a Biology major so I can help anyone with Biology. I have taken up to Ochem 1, Calc II and I'm currently taking physics but I struggle with it. If anybody would like to join this homework help group feel free to respond in this thread. We shall find people who are most skilled in each subject and they can mentor in that subject. I would like to mentor with biology however I can do chemistry as well and math up until Calc 2.

• I can help with physics

 

[Mokillem]

Hey besides E=V/d do you know any other ways to express electric field? I'm stuck on this one derivation and I can't simply use V=IR for Voltage because the Voltage can't be expressed in terms of resistance.

E= F/q
Where it's the electric force divided by the charge
If you are dealing with a point charge:
E= F/q= QK/r^2

Normally however if you want to find electric field you use Gaussian surfaces for example a plane has
E= p/e

Where p is the electric charge density and e is the electric constant.

In most non Gaussian bases question the identity
E = dV/dS ( derivative) it's an extension of your previous formula.
This can be extended To partial derivatives depending on the direction but that is more advanced.
There is also the reverse using of capacitance formula but I don't think you are asking that.

If I haven't answered the question gimme an example of what you are trying to solve .

 

[Ferrari]

Hey besides E=V/d do you know any other ways to express electric field? I'm stuck on this one derivation and I can't simply use V=IR for Voltage because the Voltage can't be expressed in terms of resistance.

Post ur book.

 

[GodKnowsBest]

Post ur book.

It asked me to derive the poynting vector of a solenoid. It does not include voltage or resistance. But I can't leave E in its regular form.

 

[Garaad Darawiish]

Hey besides E=V/d do you know any other ways to express electric field? I'm stuck on this one derivation and I can't simply use V=IR for Voltage because the Voltage can't be expressed in terms of resistance.

I can help with physics and mathematics if you need it, Post your questions

 

[Coulombs law]

@GodKnowsBest post your question

 

[GodKnowsBest]

A cylindrical solenoid of radius R and height h consists of N windings. There is a current through the windings, and this current increases with time as I=αt, where α is a constant.

Question:
Determine the magnitude of the Poynting vector at a radial distance r=R from the center of the long center axis of the solenoid.
Express your answer in terms of magnetic constant μ0, α, R, h, N and t.

 

[Mokillem]

A cylindrical solenoid of radius R and height h consists of N windings. There is a current through the windings, and this current increases with time as I=αt, where α is a constant.

Question:
Determine the magnitude of the Poynting vector at a radial distance r=R from the center of the long center axis of the solenoid.
Express your answer in terms of magnetic constant μ0, α, R, h, N and t.

According To the Gaussian method. You can find the electric field of a cylinder using the formula
E = H/(2*pi*e*R)

Where H =Q/L ( Q= charge ; L= length) charge per unit of length.

e is the electric constant

However
e= 1/(uc^2)
Where c is speed of light and u is the magnetic constant.
E =(Huc^2)/(2*pi*e*R)
Now you can find magnitude of poyting vector using formula

S= (1/u)*E*B
You can do the rest I think.

 

[GodKnowsBest]

According To the Gaussian method. You can find the electric field of a cylinder using the formula
E = H/(2*pi*e*R)

Where H =Q/L ( Q= charge ; L= length) charge per unit of length.

e is the electric constant

However
e= 1/(uc^2)
Where c is speed of light and u is the magnetic constant.
E =(Huc^2)/(2*pi*e*R)
Now you can find magnitude of poyting vector using formula

S= (1/u)*E*B
You can do the rest I think.

Thanks so much! I didn't use the Gaussian method to find E but this helps so much <3

 

[Mokillem]

Thanks so much! I didn't use the Gaussian method to find E but this helps so much <3

Glad to help

 

[Gojo Satoru]

How did the final go abaayo macaan?

I panicked during the test

 

[Foreman]

Aren't there usually study groups within college campuses? Maybe try looking for one there?

Study groups r waste of time, ppl f*ck around n take break every 10 minutes, next thing u know its 11:00pm and u didn't revise shit

Study alone

 

[GodKnowsBest]

I panicked during the test

It's okay abaayo. It's one of hundreds of tests. <3

 

[GodKnowsBest]

I just got my results back for physics 2 and I did well alhamdullilah.

Subjects I can help with:

Math- up through Calculus

Biology- basically everything that you guys might need help with unless you're a graduate student in Bio.

Chemistry- up through OChem 1

Physics- up through electricity

 

[YoungFarah]

I just got my results back for physics 2 and I did well alhamdullilah.

Subjects I can help with:

Math- up through Calculus

Biology- basically everything that you guys might need help with unless you're a graduate student in Bio.

Chemistry- up through OChem 1

Physics- up through electricity

All the subjects they say I'm too dumb for you must be really smart nacalaa

 

[GodKnowsBest]

All the subjects they say I'm too dumb for you must be really smart nacalaa

These are the core science courses though.

If you're bad at these subjects then you're basically saying you're bad at all science.

You can do well if you try hard Insha allah. Blood, sweat, and tears will take you anywhere

 

[KULTA]

That feeling when you study in finnish language and cant post anything here I had to google what calculus means Calculus= Differentiaali- ja integraalilaskenta

I've got Calculus II this year, damn i've forgotten everything

Someone use translator and tell me if this is hard or not, i've better start revising asap

 

[Hybrid]

@GodKnowsBest you must be very smart if you've taken calculus 1&2 in high school. Very few kids do that. What year are you in college ? I dropped out after taking physics 2 (electricity)