# AC vs DC Generated Magnetic Field

1. Feb 5, 2008

### cesaredu13

Good day to all, ia was trying to find info about thid topic in internet and i didn't find nothing , hope somebody can help me.

How can i find the relation between the strength of a magnetic field when i apply AC current and DC current to a coil.

in other words, how much AC current do i have to apply to a coil to have the same field strength that when i apply an x amount of DC current, in any defined point of space.

Does anybody knows a formula for this.

2. Feb 5, 2008

### wysard

It's the same. Current is current, AC or DC. The difference is in whether the field pulses once, or rotates. The peak strength is the same.

3. Feb 6, 2008

### cesaredu13

So is the same thing to apply 10 DC amps that 10 Amp rms sinosoidal signal ?

4. Feb 6, 2008

### TVP45

You can't really compare the two unless for a specific task, i.e., lifting a 100 lb weight. The 10 A dc will be constant. The 10 A ac will alternate from -14.14 A to + 14.14 A and the field will follow.