Trivia

Hard

What Are The Plastic Lumps Found On The Ends Of Computer Cables Called?

Impedance Rings
Ferrite Beads
EMI Loops
RF Clamps
A USB cable with a ferrite bead.
Stwalkerster/Wikimedia

Answer: Ferrite Beads

That clunky cylinder of hard plastic on the end of many of the cables you’ll find around your home and office—USB cables, video cables, and so on—has a specific function. Inside the hard plastic casing is a chunk of ferrite-infused ceramic designed to suppress high-frequency noise. Essentially, the ferrite bead acts as a passive low-pass filter that both blocks energy from “outside” sources that could interfere with the cable’s function and absorbs energy the cable might emit that could interfere with nearby devices. The majority of energy is absorbed by the bead and then released as tiny amounts of heat into the surrounding air.

Why is it important to suppress high-frequency noise? The noise suppression serves two primary purposes. First, it prevents electrical noise generated within a device from interfering with other components—so, for example, interference from a computer doesn’t interfere with the performance of the monitor. Second, it prevents electrical and radio energy from leaking out and interfering with surrounding equipment like television sets and radios. Ferrite beads are one of the simplest (and certainly one of the cheapest) types of interference filters to install on existing cabling, if they are called for, since you can buy cheap snap-on models that clip right over existing cables.

Trivia

Hard

Which Popular 1980s Children’s Toy Started Off As A Greeting Card Character?

Trivia

Hard

The Smell Left On Your Hands After Handling Coins Is?

Trivia

Easy

What Catapulted The MP3 Into Popular Use?

Trivia

Very Hard

Which Video Game First Inspired Widespread Controversy?

Trivia

Very Hard

Frankenstein Author Mary Shelley Carried Which Of These Mementos From Her Deceased Husband?

Trivia

Easy

Which Party Game Got Off The Ground Thanks To A Tonight Show Appearance?

Trivia

Hard

If You Are A Quatorzième, You Are A What?

Trivia

Hard

NASA Carefully Timed Space Shuttle Flights To Avoid What?

Trivia

Hard

Raccoons Were Imported To Japan By?

Trivia

Hard

The Design Of Super Mario Bros. Was Heavily Influenced By Which Novel?