# College Physics : Resistors

## Example Questions

### Example Question #1 : Circuits

You are given three resistors with known values:

You are asked to create a circuit with a total resistance of between  and . How should you arrange the resistors to accomplish this?

and  in parallel, connected to  in series

, , and  in series

, , and  in parallel

and  in parallel, connected to  in series

and  in parallel;  is not necessary

and  in parallel, connected to  in series

Explanation:

This question requires no math to correctly answer! You should not need to 'brute force' it. Although it is designed to appear time consuming, it should be relatively easily once the principle of resistors in parallel is understood. Whenever two resistors are connected in parallel, the net resistance must be less than the resistance of either of the two alone. When resistors are connected in series, the net resistance must be more than the resistance of either alone.

and  in parallel, connected to  in series - It is possible to 'eyeball' this to see that this is at least feasible.  and  in parallel must make a network with an overall resistance less than . When added in series with  (), the overall may fall between  and . To confirm, one could do the math to calculate the overall resistance, but the point of this question is to use general principles to quickly eliminate the other, incorrect answer choices.