# Magnetic field in a rotating magnet

• ctech4285
In summary, the conversation discusses the theory of magnetic fields being produced by moving electric charges. The strength of the magnetic field is proportional to the quantity and velocity of the charges. The velocity of electrons is about 1mm/s at 15A/mm~2 in copper, while the velocity of a CD spinning is about 1000RPM or 6m/s, which is 6000 times faster than the electrons. The setup involves a CD with copper wire wound around it, two contacts connected to a PC power supply, and a screwdriver with a magnetic tip that rotates when current flows through the copper coil. When the CD is spun at 6m/s, the electrons should move at 6.001m/s and

#### ctech4285

the theory

magnetic field is produced by moving electric charges
the field is proportional to the quantity and velocity of those charges

the velocity of electrons is about 1mm/s at 15A/mm~2 in copper

the velocity of a cd spinning is about 1000RPM 6m/s 6000 times more the the speed of the electrons

so if the electrons where to flow around a cd that is spinning at 6m/s the electrons should move at 6.001m/s and the field 6000 times stronger

the setup

a cd with copper wire wound around it (20windings) with two contacts (see picture) that are connected to a pc power supply at 12V results in about 2A.

the screwdriver has a magnetic tip and rotates about 45deg when current is flowing throw the copper coil wile not spinning.

the result
the screwdriver moves exactly the same amount??!

anyone has an idea? electron velocity not in the mm/s range?

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What happens to the protons when you spin the entire disc?

the protons will create the opposite magnetic field and cancel out the field generated by the electrons. thank you!

so a staticly charged spinning object should generate a magnetic field...

i got a 7kV source (ignition coil from my car). let see if i can figure out in how many electrons that translates too in CD...

## 1. What is a magnetic field?

A magnetic field is a region in space around a magnet or electric current where magnetic forces are exerted on other objects.

## 2. How is a magnetic field created in a rotating magnet?

A magnetic field is created in a rotating magnet due to the movement of electrons within the magnet. As the magnet rotates, the electrons also rotate, creating a magnetic field.

## 3. What is the direction of the magnetic field in a rotating magnet?

The direction of the magnetic field in a rotating magnet is perpendicular to the direction of the rotation. This means that the magnetic field lines are parallel to the axis of rotation.

## 4. How does the strength of the magnetic field change in a rotating magnet?

The strength of the magnetic field in a rotating magnet depends on the speed of rotation. The faster the rotation, the stronger the magnetic field will be.

## 5. What are the practical applications of a rotating magnetic field?

A rotating magnetic field has many practical applications, including in electric motors, generators, and transformers. It is also used in medical imaging technology such as MRI machines.

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