Monday, January 17, 2011

We started today's class by going over last week's homework, Transparency 25-1 and Electromagnetic Induction.

For Transparency 25-1 Worksheet, the answers are:
1. Electrical energy; battery
2. Rod with a wire coiled around it; magnetic force created by the field magnet
3. N and S poles will reverse
4. Mechanical energy from the crank
5. Electromagnetic induction as the wire moves through the magnetic field
6. EMF increases

For Electromagnetic Induction, the answers are:
1) 0.97 V
2) 1.9 x 10^-3 V
3) 0.020 V
4) 1.0 x 10^-4 V
5) 3.74 V
6) 50 turns
7) 1.8 V

Later on in the class, we also went over Lenz's Law on the Chapter 25 Study Guide. The answers for this are:
- direction
- flux
- current
- armature
- increases
- back-EMF
- decreases
- decreases

Lastly, we received a couple of handouts; Induced EMF/Factors Affecting Induced EMF, a graph of induced potential difference vs time, Lenz's Law, a worksheet to practice Lenz's law and Transparency 25-2.

Please have the worksheet for Lenz's law and Transparency 25-2 done for homework.

-- Rainer