Current Flow Basics: Bulb, Wire, Insulators

[ZapperZ]

And voltage is proportional to current so what do we get ? :)

This is a severe misunderstanding. It is a POTENTIAL DIFFERENCE, not an absolute potential value! That is what is in V=IR. The drop in the potential across a resistor is dictated by the value of the resistor itself. Do a Kirchoff Law around a simple series loop and see how you can get a consistent result even when I is a constant all around the circuit.

Zz.

 

[sgstudent]

And voltage is proportional to current so what do we get ? :)

@sgstudent No the blocks don't fall all at once the speed of Em waves is that of c or almoust c depending on the medium they are traveling but c even though the highest speed physically is still not infinite remember that.
Light and electricity travel very very fast but still they travel and it takes time and goes over a certain distance.

Oh sorry about that :) I meant they start to fall together instead of hsving one domino pushing down the next domino.

As for the formation of a lightning I read the Wikipedia article on it and I don't quite get their explanation. I don't really understand where the ionization would take place and whether the excess negative charges from the cloud actually go down the air. And where would the positive ions go (also because I'm not too sure where those ions start to form as well..)

Thanks so much for the help :) seems like this thread sparked off a lot of discussion (pun intended haha)

 

[DrZoidberg]

And voltage is proportional to current so what do we get ? :)

A constant current but different voltages across the components of the circuit.
For example. Say the battery has 10V and you have 3 resistors in series connected to it.
2 Ohm, 3 Ohm and 5 Ohm. Now the total resistance is 10 Ohm so the current is 10V/10Ohm = 1A
Voltage drop across the 2Ohm resistor is 2Ohm*1A = 2V. The 3Ohm resistor has 3V dropping over it and the 5Ohm resistor 5V. The sum of all the voltages is 10V.
If you want to include the wires into that calculation, well wires are just resistors.

 

[ZapperZ]

Oh sorry about that :) I meant they start to fall together instead of hsving one domino pushing down the next domino.

As for the formation of a lightning I read the Wikipedia article on it and I don't quite get their explanation. I don't really understand where the ionization would take place and whether the excess negative charges from the cloud actually go down the air. And where would the positive ions go (also because I'm not too sure where those ions start to form as well..)

Thanks so much for the help :) seems like this thread sparked off a lot of discussion (pun intended haha)

Unfortunately, and this is my personal opinion, it has distracted from your original question, which is really straightforward and one that I hope has been answered.

I just hope you were able to weed through the responses you received and able to figure out which ones are the correct answers to your question.

Zz.

 

[sgstudent]

Unfortunately, and this is my personal opinion, it has distracted from your original question, which is really straightforward and one that I hope has been answered.

I just hope you were able to weed through the responses you received and able to figure out which ones are the correct answers to your question.

Zz.

Yup that is true. I managed to understand the mechanism of a simple circuit and a little on lightning as a bonus. I learned that generally electrons in a circuit would all move equally around the circuit back to the other end of the battery unless the wire increases in size, then accordingly the electrons speed of movement might decrease or increase to match the current. So it allows the total electrons leaving the battery to be equal to the total number of electrons entering the battery.

Should wait to learn more about capacitors to get a better understanding before I continue asking about the mechanics of a lightning strike?

And lastly, thanks so much everyone for all their replies I gained a lot from this post Haha :)

 

[DaveC49]

The field inside the resistor is different from the one in the wire, but the field inside the wire is the same on both sides of the resistor. Potential difference is not a measure of the strength of the electric field. It is the integral of the electric field over a distance. Inside the resisitor the field is stronger because the battery is not the only field source. There is also static charge that accumulated on the surface of the wire that produces a field of it's own. At the ends of the resistor you have a "pile up" of charge. The field created by that charge strengthens the field inside the resistor but weakens it in the wire. The integral of the e. field over the entire circuit stays the same of course and is equal to the P.D. of the battery.
Inside the resistor the drift velocity may be different but after the electrons leave the resistor their velocity goes back to their previous value. The e. field is constantly transferring energy to the electrons and the electrons are constantly tranferring energy to the atoms around them. However their kinetic energy at any point in time is virtually zero. Because they move very slowly and are very light. It's like pulling a heavy object with a rope. The rope never has much kinetic energy.
Waves do not occur in a static situation i.e. when the current is constant. So no waves are being reflected.