Magnetic Field

Playing with magnets is fun.

Magnets are easily available in the market.

Some are specially designed as shown above.

Some magnets have the shape of a horse-shoe.

Magnets attract anything made up of iron, nickel, cobalt, and some other earth-metals.

If the same poles of two magnets are placed near each other, they repel. If different poles are placed near each other, they attract.

Magnets like opposite poles. south attracts north and north attracts south.

The concept of magnetic field explains the action of attraction or repulsion of the magnets.

Let's see about magnetic Field

A magnet produces a magnetic field, just like an electric charge produces an electric field.

The objects in the given region of the magnetic field are attracted or repelled by the magnet is known as its magnetic field

= is the formula for magnetic field. where F is the force experienced by the object magnetic pole strength.

Magnetic field units as above.

Magnetic fields are produced by moving charged particles which also produce an electric current.

So the flow of current also produces a magnetic field. There should be a magnetic field around the current element.

Let us discuss some properties of a magnetic field.

The direction of the magnetic field is decided by magnetic field lines.

Magnetic field lines are closed. They emerge from the north pole and terminate at the south pole.

The direction of the magnetic field at any point on the field lines is tangential to the point.

The magnetic field applies a force on moving charged particles.

Direction of magnetic force.

Magnetic force is perpendicular to the velocity of charged particles and the magnetic field.

Magnetic force can not change the magnitude of velocity but can change the direction of charged particles.

Since the magnetic force is perpendicular to the velocity, it does not do any work.

Revision

Magnetic Fields are produced by magnetic materials and flowing charges.

Current flowing through a wire produces a magnetic field around it.

Magnetic fields don’t do any work.

The End