I need help with this worksheet please, I don\'t understand the concepts with el
ID: 2302531 • Letter: I
Question
I need help with this worksheet please, I don't understand the concepts with electromagnetism, and this will help a lot! Please give detailed answers. I am offering 1500 points. Thanks in advance!!
A rod-shaped magnet is held with one end a small distance away from the center of a coil of wire attached to a voltmeter, as shown to the right. The magnet is aligned with the area vector of the coil. Shown below an' two possible graphs of the voltmeter reading as a function of time. In each case, describe how the magnet could be moved to produce the emf described by the graph. Specify which pole must be facing the coil, and discuss the direction and speed of movement.Explanation / Answer
the concept here goes is Faradays law of em inductiion.
this states that the relative motion of condcuting rod and magnetic field always induced emf (volatge) in the rod.
this law states that rate of change of magnitic flux on a conductor is always equals to the induced emf
mathematically
emf e = d(phi)/dt = AdB/dt
for N turns in the coil, it is given by
emf e= NAdB/dt
the direction of this is induced emf is given by LENZ law.this staes that the direction of induced emf always opposes its casue of motion.
so mathematically
emf e = -N AdB/dt
- sign is due to Lenz law.
remember the only situation where we will not get induced emf in the rod is both( magnetic fiedl and rod being stationary)
either of both of them changes, or both changes then we get induced emf.
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so now applying to ur situation
from Graph it is evident that emf is fluctutating between two values ( max t0 minima)
so to get this siotuation, there are three possibilties
1. making to and fro motion(SHM) of rod in uniform magnetic iedl
2. making to and fro motion (shm)of magnetic near a councting rod
3. making to and fro motion of is the (shm) of both rod and magnetic relatively opoosite to each other.
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from graph 2, there is a continuos change of emf ( only + values) this is possible my making either forward motion or backward motion of one of the two( rod or magnetic) maintainging other at rest.