Point charge

Hye~ Assalamu'alaikum~ 

This time, we will explore deeper about the magnetic field

The magnetic field of a point charge is given by:

a.Biot-Savart’s law 

 

b.Gauss’ law for magnetic fields 

c. Ampère’s law

        d.  Faraday’s law

While the magnetic field of a straight, current-carrying wire:

- Is parallel to the wire  

- Is perpendicular to the wire 

- makes a circle around the wire

- Is inside the wire.

3 D- visualization of vectors and current

(a) This is the image of vectors and current pointing into page

(b) This is the image of current into the page

Effect of a current on a compass

A magnet does not affect an electroscope

 However, a current-carrying wire will affect a magnet.

 A magnetic field, B,  is created at all points in space surrounding a current-carrying wire.  It can be thought of as an alteration of space.

The magnetic field is a vector, direction shown by the north (red) end of the compass

The magnetic field B exerts a force on magnetic poles.  The force on a north pole is parallel to B, the force on a south pole is opposite.

One of the many “right hand rules” relates direction of current to orientation of compass needles.