Electronics For Dummies, 3rd Edition

Chapter 5

Meeting Up with Resistance

In This Chapter

Using resistance to your advantage

Varying the amount of resistance

Creating just the right amount of resistance

Realizing why LEDs need resistors

If you toss a marble into a sandbox, the marble won’t go very far. But if you toss a marble onto the surface of a large frozen lake, the marble will enjoy a nice little ride before it eventually comes to a stop. A mechanical force called friction stops that marble on either surface — it’s just that the sand provides more friction than the ice.

Resistance in electronics is a lot like friction in mechanical systems: It puts the brakes on electrons (those microscopic moving particles that make up electric current) as they move through materials.

In this chapter, you take a look at exactly what resistance is, where you can find resistance (everywhere), and how you can use it to your advantage by selecting resistors (components that provide controlled amounts of resistance) for your electronic ...