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The National MagLab is funded by the National Science Foundation and the State of Florida.

Watch & Play

Watch & Play
See the science at play in these electrifying demonstrations and animations that illuminate the invisible electromagnetic forces. Or have your own fun with puzzles, games and a collection of interactive tutorials.

Interactive Tutorials
These demonstrations about laws and tools associated with electricity and magnetism allow you to adjust variables at and to visualize invisible forces — which makes them almost better than the real thing.

See-Thru Science
Seeing is believing. In these animations, we show you what electricity and magnetism might look like if they weren't invisible.

Game & Quizzes
Learn about electricity and magnetism — and have some fun while you're at it!

Science Demos
How do Maglev trains work? What are comets made of? How do bugs walk on water? This section demonstrates these and other concepts related to magnetism, electricity and other areas of science.
Read Science Stories

Read Science Stories
Whether you prefer science stories that are short & sweet, long & detailed, or in graphic form, these stories spell out the basics of electricity and magnetism and the exciting discoveries that magnets enable in easy-to-understand language.

Science simplified
Whether you prefer your science short & sweet or long & detailed, we spell it out for you here in easy-to-understand language.
Comic Collection
Read fun science stories told in comic strip style.
The Art of Science
There is beauty and art in science. Gaze on these stories of discoveries that could be featured on museum walls instead of scientific journals.

Left Fields
Explore these surprising, unconventional and sometimes downright strange stories about high magnetic field research.
Science Step-by-Step
These special science graphics explain science stories in digestible steps and include optional detours for readers wanting more background to customize your reading journey.
Explore History

Explore History
Electricity and magnetism discoveries span the centuries. Peruse the people, products and places related to electricity & magnetism from across space and time.

Pioneers
Get to know these pioneers who went down in history for their groundbreaking work, including scientists behind common terms such as Amp, Celsius, Kelvin, hertz and tesla.

Museum
From the world's first compass to the magnetic force microscope and beyond, explore a variety of instruments, tools and machines throughout history.

Timeline
Our timeline takes you through the highlights of electricity and magnetism and across the centuries.

Places
Take a field trip to these high magnetic field landmarks around the globe.
Try This at Home

Try This at Home
Science can happen anywhere! Try these hands-on science activities at home, school, club, or wherever you might find yourself! They’re easy, fun and can be done with stuff you have around the house.

Activity Books Atomic Ornament Build a Bacteria Brain Cerebrum Hat Candy DNA Candy Neuron Crystal Growing DIY Kaleidoscope Drawing Magnetic Field Lines Fill-in Fractal

Groovin Ghost Make a Compass Activity Makeshift Magnets Making Electromagnets Making Ferrofluids Möbius Strip See Iron in Food Shapeshifting Slime Solar System Hats
Plan a Lesson

Plan a Lesson
Looking for a lesson plan for science class or to incorporate science concepts into other subjects? These lessons plans offer detailed directions for K12 teachers to conduct hands-on lessons and align with next generation science standards.

Compasses Demagnetizing Electric Motors Electromagnets Magnet Exploration

Magnetic Putty Magnetizing and Unmagnetizing Making a Circuit Pancake Particles Plotting Electric Field Lines

Tape Recorder

Two heads — or even three — are better than one when it comes to understanding how tape recorders harness electromagnetic induction.

A device for recording audio signals via magnetized tape was first invented in 1935. By the late 1960s, magnetic tape cassettes were common, largely supplanting phonograph records.

Take a look at the tape recorder demonstrated here.

Current passing through tiny electromagnets generates a magnetic field above a magnetized tape. This is at the heart of how a tape recorder works.

Instructions

Note the three heads in the recorder. The Erase Head, the Record Head, and the Playback Head. Each head is a small electromagnet consisting of a coil of wire wrapped around a ring of ferromagnetic material.
See how the base of each ring has a small gap positioned directly over the tape.
The tape is a plastic film coated with minuscule magnetic particles.
When sound is picked up by the tape recorder, it’s converted to an electrical signal, which is sent to the record head.
The amplitude and frequency of the signal vary, resulting in a corresponding change in the electrical signal and the magnetic field they induce. Consequently, the magnetic particles on the tape are affected differently. Their magnetic domains shift in alignment with whatever field they pass beneath, thus imprinting a kind of magnetic picture of the audio signal on the tape.
Immediately after a signal is recorded onto tape, it can be played back using the playback head. When recorded tape scrolls under the playback head, the moving magnetic fields induce a varying current in the head. This voltage produces an electrical representation of the magnetic signal on the tape. The electrical signal is sent to an amplification/speaker system, converting the electrical energy back to mechanical energy, so that the recorded music is audible.
To erase what’s on the tape, a high amplitude, high frequency signal is sent via the wire to the erase head. The resulting magnetic field induced in the head jumbles up the magnetic particles in the tape, erasing any sound preserved in the way those particles were arranged on the tape.

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