Faradays Law Induced Voltage

Question

I'm looking for an example with answer and reasoning dealing with Faraday's Law for a Physics 2 lab.

 

The best example would be dealing with a magnet facing north and south. The equation he has is

 

V_ind = ΔΦ/Δt where Φ= BA

 

Direction of current and direction of induced magnetic field would be good examples. Also using the right hand rule.

 

An example of the changing Area would be good too. Just looking for a couple good examples of Faraday's Law in a physics 2 lab setting.

Answer 1

Christin,

 

Here's two simple setups you can use to demonstrate electromagnetic induction. Both involve loop or coil circuits.  The more turns you put into the loop the stronger will be the effect since more magnetic force lines will be "cut".

 

The objective is to create a changing magnetic field which will induce a current in the loop or coil. I'll just use the word loop from now on built from conductive wiring such as copper or aluminum.

 

Setup #1: Build a loop circuit with a loop perpendicular to the table surface, connecting the loop into a galvanometer or some current or voltage measuring instrument.  Take a strong bar magnet (with a good magnetic field) and insert it into the loop and move it back and forth. When the bar magnet is not moving inside the loop, its magnetic field is not being cut by the loop wire so no current is induced into the wire. When moving however, different magnetic lines are being intersected or "cut" by the loop wire and a current is induced at least when the magnet is being inserted and then being pulled out.

 

Setup2:  Keep the loop circuit. Replace the bar magnet with another upright loop circuit that is parallel to the first one so the loops are say 0.5 inches apart. Connect the second circuit to a switchable power source like a battery.  When you connect the battery, it sends a current around the second loop, whose magnetic field is cut by the first loop, so a current is induced into loop 1.  When you turn the battery off, the collapsing magnetic field in loop 2 also induces a response in loop 1.

 

You can work out the details: loop size, direction of current, etc.  Good luck.