# The Magnetic Field 2 Flashcards Preview

## Electricity & Magnetism > The Magnetic Field 2 > Flashcards

Flashcards in The Magnetic Field 2 Deck (16)
1
Q

What produces magnetic fields?

A

moving charges themselves

2
Q

mew naught

A

Permeability of free space

3
Q

Solenoid

A

A tightly wound helical coil of wire. When current is passed through, the magnetic field is uniform inside the helix (an electromagnet).

4
Q

Solenoid Rule

A

Curl right hand fingers in the direction of the current. Thumb points to north pole.

5
Q

N

A

of turns

6
Q

A current loop is

A

a magnetic dipole (like a bar magnet).

7
Q

r hat

A

unit vector from ds to point P

8
Q

Curl fingers in direction of B. thumb points to…

A

velocity vector/current vector

9
Q

Units of B

A

Gauss

10
Q

1 gauss =

A

10^4 T

11
Q

Ideal Solenoid

A

External field is 0, internal field is uniform

12
Q

Ideal solenoid is a great approximation when…

A

Solenoid’s length is much greater than its diameter.

13
Q

RHR for solenoids

A

Curl fingers along current, thumb = B

14
Q

Magnetic flux is always 0 for what? Why?

A

for closed surfaces. B field lines always form closed loops. Magnetic monopole does not exist.

15
Q

Current

A

Flow of positive charge

16
Q

Atomic Magnet

A

Magnetic moment due to electron’s orbital motion