×

Let's log you in.

or

Don't have a StudySoup account? Create one here!

×

or

week 7 notes 222

by: Mary-elizabeth Notetaker

6

0

4

week 7 notes 222 Phys 222

Mary-elizabeth Notetaker
U of L

Get a free preview of these Notes, just enter your email below.

×
Unlock Preview

week 7
COURSE
Fundamentals of Physics II
PROF.
Dr. Ming Yu
TYPE
Class Notes
PAGES
4
WORDS
CONCEPTS
phys, phys222, Physics, fundamentalsofphysics2
KARMA
25 ?

Popular in Physics

This 4 page Class Notes was uploaded by Mary-elizabeth Notetaker on Thursday October 6, 2016. The Class Notes belongs to Phys 222 at University of Louisville taught by Dr. Ming Yu in Fall 2016. Since its upload, it has received 6 views. For similar materials see Fundamentals of Physics II in Physics at University of Louisville.

×

Reviews for week 7 notes 222

×

×

What is Karma?

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 10/06/16
Week 7 Thursday, October 6, 2016 11:07 AM • Nichrome wire from last week melted and recast w 2x original length. Find Rn as multiple of old resistance Ro Suppose electrical wire replaced w one having every linear dimension doubled  With higher T, atoms vibrate leading to thermal scattering of electrons  Electrons find it more diff to pass thru atoms bc of more collisionsw atoms  Increased e- scattering w inc T= inc R  For most metals, R inc approx linearly w T over limited T range    Ex) platinum resistance thermometer-measures T by measuring change in resistance of conductor ○ Principle of thermometer measured by resistance formula above ○ When device is immersed in vessel containing melting indium, its resistance inc to 76.8 ohms(Rmp). Find the mp(Tmp) of indium (RoTo= 50 ohms at 20C) ○ Indium heated further until reaches 235C, what is ratio of new current I in platinum to current Imp at mp? Back to resistance formula….  Measure T coeff of resistivity  Electrical E in a circuit… power  Electrical E in a circuit… power As charge moved thru battery from A to B, pot E of system inc by: … Chem E of battery dec by same amt As charge moved thru resistor, from C to D, it loses E in collisions w the atoms in the resistor When charge returns to A, net result is some chem E of battery delivered to resistor and caused T inc …rate of E lost is power: From ohms law(delta V=IR), alternate power forms: Power unit: Watts ….I in Amperes, R in ohms, and voltage in V Kilowatt-hour: amt of time power is supplied 1kWh=3600s x 1000W=3.6x10 J 6 Ex) V applied across ends of nichrome heater wire w A and L… same V applied across ends of second nichrome heater wire w A and 2L. Which wire gets hotter? Shorter wire does bc R inc so P dec Ex) rank currents: Current proportional to power since pot diff same Current btwn pos/neg higher than thru other resistors in circuit bc power splits btwn other connected resistors but all goes back thru pos/neg part Ex) diameter of A > diameter B… lengths and resistivities are equal. For given V diff across ends, relationship btwn Pa and Pb? Pa>Pb bc diameter a larger so power dec Ex) light A 25W 120V and light B is 100W 120V…. Diff power when connected to constant 120V source Resistance of each? During what time interval does a 1C charge goes into bulb A? In what time interval does 1J pass into light A? Cost of running light A contn=inuously for 30 days assuming company sells at .11 per kWh?  Superconductors- direct drop in resistance w/out slowly going down… dec to 0 ○ Resistance os same as normal metal above certain T Tc ○ Suddenly drops to 0 at Tc

×

25 Karma

×

×

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Jim McGreen Ohio University

"Knowing I can count on the Elite Notetaker in my class allows me to focus on what the professor is saying instead of just scribbling notes the whole time and falling behind."

Jennifer McGill UCSF Med School

"Selling my MCAT study guides and notes has been a great source of side revenue while I'm in school. Some months I'm making over \$500! Plus, it makes me happy knowing that I'm helping future med students with their MCAT."

Bentley McCaw University of Florida

Forbes

"Their 'Elite Notetakers' are making over \$1,200/month in sales by creating high quality content that helps their classmates in a time of need."

Become an Elite Notetaker and start selling your notes online!
×

Refund Policy

STUDYSOUP CANCELLATION POLICY

All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email support@studysoup.com

STUDYSOUP REFUND POLICY

StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here: support@studysoup.com

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to support@studysoup.com