2. An electric circuit has a battery with an EMF of 1.50 V. Its positive terminal is connected to its negativeterminal by a copper wire in a circular loop having a radius of 0.500 m. Solve for the drift velocity in the wireif there is one free electron per copper atom.Detailed assumptions:- The size of the cell is negligible compared to the length of the circuit.- Copper resistivity: p = 1.80x10-82 – m- Copper density: D = 8.96x10³ kg – m-3- Copper relative atomic mass: m, = 63.5 g/mol%3D

2) We know that the drift velocity is given as vd= IneA---------------------- eq1 where n is no…

a bat terminal by a copper wire in a circular loop having a radius of 0.500 m. Solve f if there is one free electron per copper atom. Detailed assumptions: - The size of the cell is negligible compared to the length of the circuit. - Copper resistivity: p = 1.80x10-80 – m - Copper density: D = 8.96x10³ kg -m-

a bat terminal by a copper wire in a circular loop having a radius of 0.500 m. Solve f if there is one free electron per copper atom. Detailed assumptions: - The size of the cell is negligible compared to the length of the circuit. - Copper resistivity: p = 1.80x10-80 – m - Copper density: D = 8.96x10³ kg -m-

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 3CQ: If two different wires having identical cross-sectional areas carry the same current, will the drift...

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When a straight wire is heated, its resistance changes according to the equation R = R0 [1 + (T T0)] (Eq. 17.7), where is the temperature coefficient of resistivity. (a) Show that a more precise result, which includes the length and area of a wire change when it is heated, is R=R0[1+(TT0)][1+(TT0)][1+2(TT0)] where is the coefficient of linear expansion. (See Topic 10.) (b) Compare the two results for a 2.00-m-long copper wire of radius 0.100 mm, starting at 20.0C and heated to 100.0C.
The power dissipated in a resistor is given by P = V2/R, which means power decreases if resistance increases. Yet this power is also given by P = I2R, which means power increases if resistance increases. Explain why there is no contradiction here.
If two different wires having identical cross-sectional areas carry the same current, will the drift velocity be higher or lower in the better conductor? Explain in terms of the equation vd=1nqA by considering how the density of charge carriers n srelates to whether or not a material is a good conductor.
When a straight wire is heated, its resistance changes according to the equation R = R0 [1 + (T T0)] (Eq. 17.7), where is the temperature coefficient of resistivity. (a) Show that a more precise result, which includes the length and area of a wire change when it is heated, is R=R0[1+(TT0)][1+(TT0)][1+2(TT0)] where is the coefficient of linear expansion. (See Topic 10.) (b) Compare the two results for a 2.00-m-long copper wire of radius 0.100 mm, starting at 20.0C and heated to 100.0C.
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How does the resistance for copper and for silicon change with temperature? Why are the behaviors of these two materials different?
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Review. The healing element of an electric coffee maker operates at 120 V and carries a current of 2.00 A. Assuming the water absorbs all the energy delivered to the resistor, calculate the time interval during which the temperature of 0.500 kg of water rises from room temperature (23.00) to the boiling point.
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