Current induced magnetic field

[get_physical]

1. The problem statement
I'm doing a stimulation. Here is a picture of it.
http://desmond.imageshack.us/Himg267/scaled.php?server=267&filename=22904502.jpg&res=medium
The questions asks: when moving the voltage slider on the battery and dragging it all the way from right to left, what happens?
- compass flips or stays the same.
- magnetic field flips direction or stays the same.
- current flows in the opposite direction or in the same direction.

The Attempt at a Solution

I know that current stays the same and that the compass flips.
Since the current stays the same, does that mean the magnetic field direction stays the same? When I move it, it seems like the magnetic field lines above and below the current in the wires flips, while the area inside the coil of wire stays the same.

 

[NascentOxygen]

Hi get_physical! Why do you believe the coil current stays the same when you reduce the voltage across the coil?

Perhaps I haven't appreciated a marvel of simulated batteries: does one end of the slider deliver positive voltage, and when slid all the way to the other end deliver negative voltage??

 

[NascentOxygen]

When I move it, it seems like the magnetic field lines above and below the current in the wires flips, while the area inside the coil of wire stays the same.

I'm wondering how you know what seems to be happening inside the coil--you can't see any field arrows in there, can you?

 

[get_physical]

Thanks so much for your reply. I didn't know it was the wrong slider that i was sliding.
Now i know that the current changes and that the compass flips. So does the magnetic field also flip direction? I'm guessing yes, but not totally sure.

 

[asteriatic]

[/b]

Thank you for sharing your simulation and questions. From the image provided, it looks like you are studying the concept of current induced magnetic fields using a coil of wire and a battery. Based on your observations, it seems that when the voltage slider is moved from right to left, the compass flips and the magnetic field lines above and below the current in the wires also flip. This is likely due to the changing direction of the current in the wires.

To answer your questions, the direction of the magnetic field is determined by the direction of the current. When the current flows in one direction, the magnetic field lines will have a certain orientation. When the current flows in the opposite direction, the magnetic field lines will flip to the opposite orientation. This is known as the right-hand rule, where if you point your right thumb in the direction of the current, your fingers will curl in the direction of the magnetic field lines.

In this case, as you move the voltage slider from right to left, the current in the wires will also change direction, causing the magnetic field lines to flip. However, the overall strength of the magnetic field should remain the same. This is because the current is still flowing through the same coil of wire, and the strength of the magnetic field is directly proportional to the current.

I hope this helps to clarify the relationship between current and magnetic fields in your simulation. Keep exploring and experimenting to deepen your understanding of this concept.