Magnetic fields are really important for the electronics we use every day. They not only help devices work better but also are key to how many of them function.

1. Electronic Parts That Use Magnetic Fields

Here are some important electronic parts that rely on magnetic fields:

• Inductors: These are found in many circuits. Inductors store energy using magnetic fields when electricity flows through them. How well they store energy is called inductance, measured in henries (H). Most inductors have values from $10 \, \mu H$ (microhenries) to several hundred henries.

• Transformers: Transformers change electrical energy from one voltage level to another by using magnetic fields. For example, a small transformer might have a turns ratio of $1:2$. This means that if the first coil has 100 turns, the second coil could have 200 turns, which increases the voltage.

• Speakers: Speakers work with magnetic fields created by permanent magnets and coils. They turn electrical signals into sound waves, which is based on a principle called electromagnetic induction.

2. How Magnetic Fields Are Used in Data Storage

Magnetic fields are key in devices that store data:

• Hard Disk Drives (HDDs): These drives use magnetic fields to read and write data on disks. HDDs can hold a lot of information, sometimes over $10 \, TB$ (terabytes). The read/write heads hover only a few nanometers above the disks.

• Magnetic Tape: This type of storage is used for keeping data safe. A single magnetic tape cartridge can hold up to $20 \, TB$ of data. It works by using magnetic fields to arrange small particles on the tape.

3. Magnetic Fields in Our Daily Lives

Magnetic fields are everywhere in electronics:

• Devices we use every day, like smartphones, TVs, and computers, all have parts that use magnetic fields.
• In a typical home, you can find several devices that work with magnetism, using around $10 \, kWh$ of power each day. This shows just how common these technologies are.

In short, magnetic fields play a vital role in how modern electronic devices work and help define our everyday technology.