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andrewwski wrote:

bluejay wrote:I have a little problem with voltage drops. How do you find it out?

That depends on the circuit and the component. But generally a combination of Ohm's Law or Kirchoff's Laws.

Is there a difference between total voltage drop and voltage drop?

andrewwski wrote:

bluejay wrote:I have a little problem with voltage drops. How do you find it out?

That depends on the circuit and the component. But generally a combination of Ohm's Law or Kirchoff's Laws.

so..what if a problem states that a 4.0 ohm resistor, a 8.0 ohm resistor, and a 10.0 ohm resistor are connected in series across an 11-V battery, what is the total volatage drop across the 4.0 ohm and 8.0 ohm resistors? and how do you find it out?

bluejay wrote:

andrewwski wrote:

bluejay wrote:I have a little problem with voltage drops. How do you find it out?

That depends on the circuit and the component. But generally a combination of Ohm's Law or Kirchoff's Laws.

so..what if a problem states that a 4.0 ohm resistor, a 8.0 ohm resistor, and a 10.0 ohm resistor are connected in series across an 11-V battery, what is the total volatage drop across the 4.0 ohm and 8.0 ohm resistors? and how do you find it out?

One method would be to replace all three resistors with a single 22.0 ohm resistor. Applying Ohm's law, you know that there is a 0.50 ampere current across the resistor. Since there are not any nodes in the middle, KCL tells you that this 0.50 ampere current will flow through all three resistors. You can then apply Ohm's law again to calculate that across the 12.0 ohm equivalent resistor (4.0 and 8.0), V=0.50*12.0 ohms would be 6.0 volts. You could also solve it as a voltage divider between the 12.0 equivalent and the 10.0 ohm resistor to get the same answer.

wow...i never thought about it that way...now i get it.

More info at http://physics.bu.edu/py106/notes/Circuits.html

What exactly is the coulomb and how do you find it out?

You could for example look it up on wikipedia. It is a unit of electrical charge. An ampere is a coulomb per second and a volt is a joule of potential energy per coulomb charge.

what are the electromagnetic principles?

Also, how do magnetic fields work?

what is a good website or resource for this event? so many different resources online sort of got me lost. Please help.