5- chapter27-question4 A certain wire has resistance R. Another wire, of the same material, has half the length and half the diameter of the first wire. The resistance of the second wire is: Option1 Option2 Option3 Option4 Option5 R/4 R/2 2R 4R a) Option4 b) Option5 201142 Option2 d) O Option1 Option3

5- chapter27-question4 A certain wire has resistance R. Another wire, of the same material, has half the length and half the diameter of the first wire. The resistance of the second wire is: Option1 Option2 Option3 Option4 Option5 R/4 R/2 2R 4R a) Option4 b) Option5 201142 Option2 d) O Option1 Option3

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 27CQ: Why is the resistance of wet skin so much smaller than dry, and why do blood and other bodily fluids...

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Similar questions

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Does the resistance of an object depend on the path current takes through it? Consider, for example, arectangular bar—is its resistance the same along its lengthas across its width?
Unreasonable Results Suppose you have a 40.0- galvanometer with a 25.0-A sensitivity, (a) What resistance would you put in series with it to allow it to be used as a voltmeter that has a full-scale deflection for 0.500 mV? (b) What is unreasonable about this result? (c) Which assumptions are responsible?
Analog meters use a galvanometer, which essentially consists of a coil of wire with a small resistance and a pointer with a scale attached. When current runs through the coil, the pointer turns; die amount the pointer turns is proportional to the amount of current running through the coil. Galvanometers can be used to make an ammeter if a resistor is placed in parallel with the galvanometer. Consider a galvanometer that has a resistance of 25.00and gives a full scale reading when a 50A current runs through it. The galvanometer is to be used to make an ammeter that has a full scale reading of 10.00 A, as shown below. Recall that an ammeter is connected in series with the circuit of interest, so all 10 A must tun through the meter, (a) What is the current through the parallel resistor in the meter? (b) What is the voltage across the parallel resistor? (c) What is the resistance of the parallel resistor?
Why is the resistance of wet skin so much smaller than dry, and why do blood and other bodily fluids have low resistances?
Unreasonable Results (a) What resistance would you put in parallel with a 40.0- galvanometer having a 25.0-A sensitivity to allow it to be used as an ammeter that has a full-scale deflection for 10.0? (b) What is unreasonable about this result? (c) Which assumptions are responsible?