P219lecture11inductors

# - Goal To understand uses for induction Objectives 1 To learn how to use Lenzs Law to determine the direction of an induced current or magnetic

This preview shows pages 1–4. Sign up to view the full content.

Goal: To understand uses for induction Objectives: 1) To learn how to use Lenz’s Law to determine the direction of an induced current or magnetic field 2) To learn how to use Transformers 3) To learn about Inductors 4) To be able to calculate the Energy stored inside an inductor 5) To learn about LR circuits

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Lenz’s Law V = - N Δ Φ / Δt This is for a coil. If the magnetic field decreases then we will produce a positive EMF. An increase in the magnetic field likewise will produce a negative EMF. The magnetic field induced from the EMF produces a magnetic flux which counteracts the change in magnetic flux! So, when the magnetic field increases (in the + direction) you induce a negative magnetic flux from the current which gives a clockwise current. A decreasing magnetic field (in the + direction) induces a counter-clockwise current (which produces a positive magnetic flux). Note: if you change a negative magnetic field then you have to notice that an increased magnitude is really decreasing the magnetic field. Bottom line is find the current which produces a magnetic field which offsets the change in the magnetic field.
Example: From HW 6: A coil rests upright on your desk. A magnetic field which is at a 90 degree angle to your desk causes a clockwise current in the coil. What must be true about the direction and magnitudes of

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 12/01/2010 for the course PHYSICS 21900 taught by Professor Rhoads during the Spring '10 term at IUPUI.

### Page1 / 14

- Goal To understand uses for induction Objectives 1 To learn how to use Lenzs Law to determine the direction of an induced current or magnetic

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online