Just wanted to see if anyone could check my work. I only have 1 opportunity to do this. Thanks yall!(adsbygoogle = window.adsbygoogle || []).push({});

1.) Suppose that you wish to fabricate a uniform wire out of 1.00g of copper. If the wire is to have a resistance of R=.5Ω and if all of the copper is to be used, what will be (a) the length and (b) diameter of this wire?

a) L = [(1 x 10^-3)(.5)/(8.92 x 10^3 x 1.7 x 10^-8)]^1/2 = 1.82m

b) D = 2 (6.19 x 10^-8 / ∏ ) ^1/2 = 2.8 x 10^-4 m

2) The power supplied to a typical black-and-white television set is 90W when the set is connected to 120V. (a) How much electric energy does this set consume in one hour? (b) A color television set draws about 2.5A when connected to 120V. How much time is reuiqred for it to consume the same energy as the black-and-white model consumes in one hour?

a) E = 90x3600= 3.24 x 10^5 J = .09kWh

b) = R = 6.25 x 48 = 300 W 3.24 x 10^5 = 300t

t = 1080sec = 18min

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Resistivity & Electrical Energy

**Physics Forums | Science Articles, Homework Help, Discussion**