1 / 20

Exam I coming up Feb 24 th ! (a week from TODAY)

Exam I coming up Feb 24 th ! (a week from TODAY). 5 multi-choice 10 pts /each . TEST FORMAT?. At least 1 ( maybe 2) bonus multi-choice 5 pts /each . (one may be a HW problem!).

kenda
Télécharger la présentation

Exam I coming up Feb 24 th ! (a week from TODAY)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. ExamI coming up Feb 24th!(a week from TODAY) 5 multi-choice 10 pts/each TEST FORMAT? At least 1 (maybe 2) bonus multi-choice 5 pts/each (one may be a HW problem!) 2 written problems (partial credit!) 25 pts/each Cheat Sheet! Sample on web site: you’ll get one with the test HW3 due on Friday: P.S. or Review?

  2. I = 2800 A (!) 4 cm V = ?

  3. Real vs. idealized electric circuit (next)

  4. Real electric circuit V = + 1.50 V 2 ft I Resister R = 220.0000 W 22 AWG wire Diameter = 0.025 in R/L = 0.0161 W/ft Define V = 0 here ! 3 ft

  5. Idealized electric circuit (perfect wires) Perfect wires! (R = 0) V = + 1.50 V I R = 220.0000 W V = 0 V VR = I =

  6. Real electric circuit V = + 1.50 V RW2 = 2 ft + R = 220.0000 W 22 AWG wire Diameter = 0.025 in R/L = 0.0161 W/ft Define V = 0 here ! 3 ft RW3 = Assume RT = RW2+R + RW3 = THEN I = V/RT

  7. Real electric circuit V = + 1.50 V RW2 = 0.0322 W VW2=I RW2 = + VR=I R = 220.0000 W VW3=I RW3 = Define V = 0 here ! RW3 = 0.0483 W

  8. But, What’s the voltage drop along a 100 ft long cable (18 AWG) when it’s carrying 20 A? (18 AWG: 0.00639 W/ft)

  9. Voltage drop along wires! (18 AWG: 0.00639 W/ft) 20 A 110 V 20 A 100 ft

  10. Electric Power

  11. Electric Power But I is the same throughout the circuit!

  12. I constant → HEAT! power lost as heat

  13. Electric Power I V Units?

  14. Electric Power If R is not to burn up. It must be able to dissipate heat at a rate of V×I

  15. FROM the Basics You can derive ….

  16. Lame resistor demo Example: Big guy is rated as 10  with max current of 6.5 Amps. What is the max power rating? Max voltage across it? Less-Lame fuse demo

  17. Example: 18.30 A 115-V fish-tank heater is rated at 110 W. Calculate a) the current through the heater when it’s operating, and b) its resistance.

More Related