Physics current question?

Question

How do i find the current through, and voltage across hte resisters in a circuit when looking at a diagram (in simple get-the-right-answer terms, im not good at physics)

Answer 1

Voltage= Current X Resistance
V=IR => if you want current, it will be V/R

in the diagram, they will gove you the resistances and the voltage. if the resistors are in series, you will simply add them up together, and devide the voltage by thr sum of resistances to get the current.

But if they are parallel, the total R is found by the following formula: 1/R = 1/R1 + 1/R2. Then again you find the total R and put it in the first formula.

thats all you need to know about it :-) simple and easy. Good luck

Answer 2

It depends on the circuit, how well you'll be able to determine the voltage across it, or current through it. There's different ways to determine this, based on the circuit. If you have something in parallel with the resistor, the voltage across the resistor in question is going to be the same as the voltage of whatever is in parallel with it. If you have 2 or more resistors in series, then you must do a voltage division, where the voltage across the resistor in question is going to be a ratio of the overall voltage and the resistances of the items in series.

Once you find the voltage across, you can just divide that voltage by the resistance value of the resistor in question.

I'd give you simple get-the-right-answer terms, but you didn't give an example circuit to tell you how.

Answer 3

You really need to look at the context. A resistor that is part of other devices often does not have obvious i or v values by inspections. However, if a problem gives you the voltage across a resistor, the current through it is v/R and if the current is given then the volatage drop across the resistor is iR. Clearly, (or maybe not so clearly) different expressions of Ohm's law.