Chapter 30 Lecture 10 7 October 2014

Current and Resistance

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A certain copper wire has a resistance of 10 Ohm. At what point along its length the wire be cut so that the resistance of one piece is 4.0 times the resistance of the other? What is the resistance of each piece?

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Problem 14. 2.0x1013 electrons flow through a transistor in 1.0 ms.

What is the current through the transistor?

Example. A service station charges a battery using a current of 6.7-A for 5.0 h.

How much charge passes through the battery?

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Conceptual question 9. The wire in the figure consists of two

segments of different diameter but made from the same metal.

Compare currents, I1 and I2a)

Compare the current densities, J1 and J2b)

Conceptual question 6. Rank in order from largest to smallest

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