Why Does the Same Current Flow Through Every Segment of a Wire?

  • Thread starter Thread starter deepankvora
  • Start date Start date
  • Tags Tags
    Doubt Electricity
deepankvora
Messages
10
Reaction score
0
Curent Electricity Doubt! PLEASE HELP!

Homework Statement


I did not understand one thing.. If it is given that a wire has a current 'i', then why do we say (in applications of laws such as biot savart law) that the current in a small element of the wire is also 'i', that is the same current that passes through the whole conductor.


Homework Equations


can someone explain this. i got really confused on this one.


The Attempt at a Solution


I thought we should take current in the ' dl ' element of the wire as ' di ' and not i. I am wrong. Please Explain, anyone!
 
Last edited:
Physics news on Phys.org


Current is \frac{dQ}{dt}, the amount of charge which passes through a cross-section of the wire per unit time. This value does not depend on the length segment of wire.

Also, for one segment of wire to have a different current than another causes a buildup of charge, inconsistent with Kirchhoff's junction rule.
 

Thread 'Initial conditions for orbits around a wormhole'

Hi, I had an exam and I completely messed up a problem. Especially one part which was necessary for the rest of the problem. Basically, I have a wormhole metric: $$(ds)^2 = -(dt)^2 + (dr)^2 + (r^2 + b^2)( (d\theta)^2 + sin^2 \theta (d\phi)^2 )$$ Where ##b=1## with an orbit only in the equatorial plane. We also know from the question that the orbit must satisfy this relationship: $$\varepsilon = \frac{1}{2} (\frac{dr}{d\tau})^2 + V_{eff}(r)$$ Ultimately, I was tasked to find the initial...
View full post »

Thread 'Help to convert units of a simple formula'

The value of H equals ## 10^{3}## in natural units, According to : https://en.wikipedia.org/wiki/Natural_units, ## t \sim 10^{-21} sec = 10^{21} Hz ##, and since ## \text{GeV} \sim 10^{24} \text{Hz } ##, ## GeV \sim 10^{24} \times 10^{-21} = 10^3 ## in natural units. So is this conversion correct? Also in the above formula, can I convert H to that natural units , since it’s a constant, while keeping k in Hz ?
View full post »

Similar threads

Magnetostatics and Ampere's law on a finite length wire
Replies
5
Views
3K
Infinitely long cylindrical shell (magnetic field at centre)
Replies
1
Views
5K
Changing cross-sectional area effect on induced current
Replies
10
Views
5K
How Does the Biot-Savart Law Apply to a Wire Segment with a Circular Arc?
Replies
4
Views
4K
Why is current constant through a resistor?
Replies
11
Views
1K
Why can current be larger than placed charges in a wire?
Replies
1
Views
2K
Electric field around a current carrying wire.
Replies
1
Views
3K
I Can current flow in an open circuit?
Replies
4
Views
3K
Direction of Magnetic Field Outside a Cylindrical Wire
Replies
4
Views
2K
Why Doesn't Electric Force Cause Wires to Move?
Replies
15
Views
2K

Hot Threads

Recent Insights

Back
Top