### Present Remotely

Send the link below via email or IM

• Invited audience members will follow you as you navigate and present
• People invited to a presentation do not need a Prezi account
• This link expires 10 minutes after you close the presentation

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

# F16 PH333 7.2.3-7.2.4

No description
by

## Richard Datwyler

on 11 December 2018

Report abuse

#### Transcript of F16 PH333 7.2.3-7.2.4

Induction
7.2.3 Inductance
7.2.4 Energy in Magnetic Fields
Mutual inductance
Two loops of wire.
One induces a current from the B field of the other
Key equations and ideas
Newmann formula
M is purely geometric
reverse roles of 1 and 2
Self inductance
now if that second loop is actually attached to the first, then we would call it self inductance.
It is measured in Henries.
Purely geometric as well... just like resistance and capacitance
Always opposed change, we call it back emf.
square lope sides a, lies midway between 2 wires 3a apart. A clockwise current I is in the little loop increasing gradually and constant( ). Find emf in big loop and direction.
Energy
When you turn up the current it creates a back emf that you have to work against. The value of work is:
or, another way you can discuss the work in a circuit as being stored in the magnetic field. Both work fine.
A source, inductor and resistor are in series long time.
Now a switch thrown and only inductor and resistor. What is current at time t, total energy to resistor, and total energy stored in inductor?
run problem backwards.
flux from the lower wire
total flux and M