One Wire, Ten Times the Power!? Feel a “30-Amp” Magnetic Field with the Pascal Cable (S-Cable)
I’m Ken Kuwako, a science trainer. Every day is an experiment.
“Electricity” and “magnetism.” Do you remember learning about the “right-hand screw rule” and “Fleming’s left-hand rule” in school science?
They’re familiar concepts from textbooks, but when you actually try the experiments, the compass needle may only twitch “a little,” or a wire may move “ever so slightly.” Honestly, it can be hard to experience the kind of dramatic effect that makes you say, “Wow!” The reason is simple: the forces involved in electricity and magnetism can be surprisingly delicate and weak.
But what if you could safely experience an electromagnetic phenomenon with the kind of “wow factor” you would expect from a current of tens of amperes, while still using a safe school laboratory power supply capable of only a few amperes? Today, I’d like to introduce an amazing piece of experimental equipment called the “Pascal Wire” and reveal the secret behind its astonishing “10× power”!
The Dilemma of Electromagnetism Experiments
The fact that electricity can produce magnetism, as discovered by Oersted, and that a current experiences a force in a magnetic field, as described by Fleming’s law, are fundamental principles behind modern motors and generators.
However, to make these forces clearly visible in an experiment, you would normally need a current of “tens of amperes”—enough to trip an ordinary household circuit breaker. In school laboratories, the available current is usually limited to around 5 amperes at most. That simply isn’t enough for the effects to be easy to see.
The “Pascal Wire” solves this long-standing dilemma with a surprisingly clever idea.
The “Pascal Wire (S-cable)” is the world’s only experimental teaching device that allows anyone to easily, safely, and affordably experience at hand all kinds of electromagnetic phenomena, beginning with Oersted’s great discovery.
The Secret Is “10 Wires”! How It Safely Creates 10× the Effect
With the Pascal Wire, for example, you can create a magnetic field as powerful as one produced by a “50-ampere” current simply by running 5 amperes from a laboratory power supply.
You might be thinking, “Wait, isn’t 50 amperes dangerous?” But here’s the key: it’s only like having 50 amperes flowing. The actual current flowing through the equipment remains just 5 amperes. That’s what makes it so safe. “I have no idea what you’re talking about!” Right? (Haha.)
The secret lies in the construction of the wire. The Pascal Wire looks like a single thick cable, but inside it are actually 10 separate thin wires.
I immediately ordered some online and bought the cable needed to make one. Suitable cable for making a Pascal Wire includes Fujikura Densen VCTF 0.3sq × 10-core, which is available on Amazon.
Fujikura Densen VCTF 0.3sq × 10-core Vinyl Cabtire Cord (Round Cable)
Inside are 10 separate wires like these. They are soldered together in different combinations according to their colors.
These 10 wires are carefully connected by soldering so that “the current entering from (+) travels through the 10 wires in parallel (!) and exits through (−).” ※A single conductor is connected in series so that it makes 10 back-and-forth passes. The key idea is to “combine the effects of all 10 wires.”
(※Update: For the exact internal structure, please check the official website. The important point is that current flows through all 10 conductors, causing the magnetic fields produced by each conductor to “add together”!)
And this is what it looks like when finished.
If we call the magnetic field produced by a 3-ampere current in a single wire “1,” the Pascal Wire creates essentially the same effect as having 3 amperes flowing through each of 10 wires—all inside a single thick cable.
That means the magnetic field (and the force produced) is simply 10 times stronger! Instead of relying on the brute force of an enormous current, this clever idea combines the effects of 10 wires to create experiments that are both safe and impressively powerful.
Let’s stack two power supplies and try running a larger current. The effect becomes 10 times stronger again. As an example, you can use the following link as a reference for an experiment demonstrating the right-hand screw rule.
It’s fun to watch the compass needle suddenly twitch!
This, for example, is an experiment demonstrating Fleming’s left-hand rule. The Pascal Wire is suspended loosely and passed between the poles of a U-shaped magnet. The moment you switch on the current…
You can clearly see the wire swing with a big, sudden “jerk!” It’s one of those moments when you can actually feel the force with your own eyes and body.
When you switch to alternating current, the moving wire vibrates rapidly. In this way, the Pascal Wire is a wonderful teaching tool that lets students safely and dynamically experience the mysterious invisible world of “electricity” and “magnetism” with their own bodies.
Questions, Requests, and Collaborations
I want to bring the wonder and excitement of science a little closer to everyone! I share fun science experiments you can try at home, along with easy-to-understand tips and tricks. Have a look around and search for whatever catches your curiosity!
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