Lecture 29  iq25

 

1. Velocity selector

2. Hall effect: h2: 006-010

o   Experiment which determines the sign of the carrier charge.

o   Direction of Hall current

o   Calculate the Hall voltage

o   Relationship between number density and the mass density.

o   One mole has

§  the molar mass M, and

§  the total # of free electrons =(# valence electrons)N­A.

3. Sliding bar

o   Magnetic force ahd polarized charges

o   plalrization field, sign of emf.

o   Mechanical power =electric dissipative power

4. Hint on two problems in h3

o   002

o   Magnetic force and polarized charges

o   Direction of the emf is determined by the direction of the magnetic force

o   016 emf generated in a rotating loop

Announcement:

Learning module:

Feedback will be incorporated into the lecture.

The learning modules will count as part of the homework score: instead of homework accounting for 15%, we now have homework at 12% and leaning modules at 3%.

Feedback on homework: This feedback will be used as the basic content for discussion sessions. In order to encourage participation, we have made HW feedback part of the iq clicker credit:

o   iq clicker now counts for 5%,

o   while feedback counts for 2%.

The latter is an easy 2%, as all you need to do is tell us which problem you found most confusing on a particular assignment and why. The feedback will be due on the same evening the homework is due, but the due time will be 11:50 to give those last-minute types a chance to enter feedback after completing the homework.

Words from Josh: “Please note that I will be reading the feedback, so if you enter something like "no comment" or a random string of keystrokes, you will not receive credit. Please make a sincere effort to give quality feedback, as it will have a direct effect upon the quality of your instruction.”