Ch20 HW2 - Ch20 HW2 F2010 12/17/10 9:23 PM Stefan Coreth PY...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
12/17/10 9:23 PM Ch20 HW2 F2010 Page 1 of 5 http://www.webassign.net/v4cgisacoreth@ncsu/student.pl?y=20101218022310sacoreth@ncsu6657124101 Current Score : 18.75 / 20 Due : Monday, October 18, 2010 11:25 AM EDT 1. 2/2 points Question: MI3 20.1.X.049 (a) Suppose you charge a 3.0 F capacitor with two 1.5 volt batteries. How much charge was on each plate? 9 9 C (b) How many excess electrons were on the negative plate? 5.625e19 5.62e+19 electrons 2. 2/2 points Question: MI3 20.2.X.064 (a) In gold at room temperature, the mobility of mobile electrons is about 4.3 10 -3 (m/s)/(V/m), and there are about 5.9 10 28 mobile electrons per m 3 . Calculate the conductivity σ . In actual practice, it is usually easier to measure the conductivity σ and deduce the mobility u from this measurement. 40592000 4.06e+07 (b) What are the correct units for σ ? 3. 1/1 points Question: MI3 20.2.X.065 Consider a magnesium wire ( σ = 2.2 10 7 ) with a cross-sectional area of 1 mm 2 (similar to your connecting wires) and carrying 0.3 amperes of current, which is about what you get in a circuit with a round bulb and two batteries in series. Calculate the strength of the very small electric field required
Background image of page 1

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

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 5

Ch20 HW2 - Ch20 HW2 F2010 12/17/10 9:23 PM Stefan Coreth PY...

This preview shows document pages 1 - 2. Sign up to view the full document.

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