Phy122_0907 - Physics 122 This Thi course is hard! i h d!...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon
Physics 122 September 7, 2010 This course is hard! Don’t expect to cram all the material before exams. It is important to keep up with the material, and not slip behind. You should definitely look at the homework problems before coming to class. mw p m f m g . Labs start next week (Sept. 13-15). ou should read the lab materials before coming to You should read the lab materials before coming to lab, and take the pre-lab quiz. Lab writeup and pre- lab-quiz will be on your section of PHY124 in Blackboard as soon as a software glitch is resolved. There will generally be clicker questions each Thurday ased on that week’s lab based on that week s lab. Question 1
Background image of page 1

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

View Full DocumentRight Arrow Icon
Here is how the WebAssign gradebook looked yesterday at ~1:30 PM. D = Not Downloaded Students ND = Not Downloaded. who haven’t even looked at the problems. NS = No Submissions. Students who downloaded, but haven’t submitted any of the problems for grading. Original policy of 10% credit subtracted for wrong answers has been canceled. You have 10 “free” tries for each problem
Background image of page 2
As of 3:00 PM today, more than 80% of you have not yet ownloaded the Chapter 16 homework problems Not good! downloaded the Chapter 16 homework problems. In the first homework assignment, 10% credit was lost for ach incorrect answer We have changed that so there is each incorrect answer. no penalty for incorrect answers. Question #2. Charges 1 and 2 have 1 2 what signs? Answer: 1 is +, 2 is -
Background image of page 3

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

View Full DocumentRight Arrow Icon
Question 3: If there are two large planes of charge, negative on the left and positive on the right, for an observer between the sheets of charge, what is e direction of the electric field? the direction of the electric field? -- + -- + -- + -- + -- + -- + -- + -- P Answer: field + -- + -- + points to the left -- + -- +
Background image of page 4
Conductor: a material in which charges are free to move.* Put a charge next to a conductor: How do the field lines look? ? Question 4: What’s wrong with this picture?
Background image of page 5

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

View Full DocumentRight Arrow Icon
Electric field lines meet a conductor erpendicular to the perpendicular to the surface. - - - - - - - - - - - - - - WRONG. Charges on the - - - - - - conductor would move in response to the field.
Background image of page 6
If the conductor arries a net negative If the conductor carries carries a net negative charge zero net charge - - + + + - - - - - - - - - - - - - + + + - - - - - - - - - - - - - - + + + + - - - - - - - - - - - + + + + +
Background image of page 7

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

View Full DocumentRight Arrow Icon
Remember some concepts about potential energy from Physics 121. In this room, there is a gravitational field that exerts a force F = mg (vector) pointing downward on an object with mass m . The amount of work required to carry the B object from A to B is W= m g (h -h A ) , independent F= m g of the path . h here is a (scalar) gravitational There is a (scalar) gravitational potential energy U= m g h . nly ifferences potential Only differences in potential energy are meaningful.
Background image of page 8
If you carry a particle with charge +q around in a place where there is a uniform electric field E , say pointing in e x direction the charge feels a force the x the x direction, the charge feels a force F= q e in the x direction.
Background image of page 9

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

View Full DocumentRight Arrow Icon
Image of page 10
This is the end of the preview. Sign up to access the rest of the document.

This document was uploaded on 10/18/2010.

Page1 / 33

Phy122_0907 - Physics 122 This Thi course is hard! i h d!...

This preview shows document pages 1 - 10. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online