Pencil "lead" is actually mostly graphite (Carbon). You need a 4 Ohm resistor but only have 0.7 mm diameter mechanical pencil lead available. A. How long of a peice of this graphite do you need to make a 4 Ohm resistor? B. What current will pass through this resistor when connected to a 1.5 V battery? TABLE 27.2 Resistivity and conductivity of conducting materials Resistivity Conductivity Material (N m) (N-'m-') Aluminum 2.8 × 10 8 3.5 x 107 |Copper Gold 1.7 × 10-8 6.0 × 107 2.4 × 10-8 4.1 × 107 Iron 9.7 × 10-8 1.0 × 107 Silver 1.6 × 10-8 6.2 × 107 Tungsten Nichrome* 5.6 × 10~8 1.8 × 107 1.5 × 106 6.7 × 10$ Carbon 3.5 × 10-5 2.9 × 104 *Nickel-chromium alloy used for heating wires.

Pencil "lead" is actually mostly graphite (Carbon). You need a 4 Ohm resistor but only have 0.7 mm diameter mechanical pencil lead available. A. How long of a peice of this graphite do you need to make a 4 Ohm resistor? B. What current will pass through this resistor when connected to a 1.5 V battery? TABLE 27.2 Resistivity and conductivity of conducting materials Resistivity Conductivity Material (N m) (N-'m-') Aluminum 2.8 × 10 8 3.5 x 107 |Copper Gold 1.7 × 10-8 6.0 × 107 2.4 × 10-8 4.1 × 107 Iron 9.7 × 10-8 1.0 × 107 Silver 1.6 × 10-8 6.2 × 107 Tungsten Nichrome* 5.6 × 10~8 1.8 × 107 1.5 × 106 6.7 × 10$ Carbon 3.5 × 10-5 2.9 × 104 *Nickel-chromium alloy used for heating wires.

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter20: Electric Current, Resistance, And Ohm's Law

Section: Chapter Questions

Problem 39PE: Unreasonable Results (a) To what temperature must you raise a resistor made of constantan to double...

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