You are given a wire of length I and cross-section area A. You put a potential difference of V across it and measure the current I that runs through it. You then cut the wire in ha lengthwise and solder the ends together, constructing a wire with twice the length as the original. You again put a potential difference V across the wire. In terms of the original quantities, 1. What is the resistance of the new wire? 2. What is the current through the new wire? 3. What is the current density through the new wire? 4. What is the electric field through the new wire?

You are given a wire of length I and cross-section area A. You put a potential difference of V across it and measure the current I that runs through it. You then cut the wire in ha lengthwise and solder the ends together, constructing a wire with twice the length as the original. You again put a potential difference V across the wire. In terms of the original quantities, 1. What is the resistance of the new wire? 2. What is the current through the new wire? 3. What is the current density through the new wire? 4. What is the electric field through the new wire?

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter21: Current And Direct Current Circuits

Section: Chapter Questions

Problem 9P

See similar textbooks

Similar questions

A 12-guage gold wire has a length of 1 meter. (a) What would be the length of a silver 12-gauge wire with the same resistance? (b) What are their respective resistances at the temperature of boiling water?
A 50.0 - g sample of a conducting material is all that is available.The resistivity of the material is measured to be 11 x 10-8 Ω ⋅ m,and the density is 7.86 g/cm3. The material is to be shapedinto a solid cylindrical wire that has a total resistance of 1.5 Ω.(a) What length of wire is required? (b) What must be thediameter of the wire?
A long wire with a radius of 0.400 cm carries a current. The porential difference across a 3.60 m long section of this wire is 12.0 V, and the wire carries a current of 0.370 A. a. What is the resistance of the 3.60 m long section of wire? b. What is the resistivity of the wire?
A 520-Ω resistor is connected to a variable-voltage power supply. (a) What voltage is necessary to cause a current of 0.4 A in the resistor? (b) What current flows in the resistor when the voltage is 21 V?
A 30.0 m long extension cord is made from two #19 gauge copper wires. (a) What is the resistance of the wire at 200C? The diameter of the copper wire is 0.912 mm.(b) If the copper wire is replaced by an Aluminium wire of the same length, what is the diameter so that the new wire has a resistance no greater than the old?
A copper wire has a diameter of 2.0 mm and a length of 3.0 m. It carries acurrent of 6.3 A. The density of free electrons in copper is 8.5×1028electrons per cubic meter and resistivity of copper is 1.7×10-8Ω.m.a) What is the current density in the wire?b) What is the resistance of the wire?c) What is the electric field in the wire?d) What is the drift velocity of free electrons? Or calculatethe drift velocity of free electrons (or find the drift velocity of freeelectrons)e) Find the power dissipated as heat in the wire
A carbon resistor at room temperature (20 °C) is attached to a 9.00-V battery and the current measured through the resistor is 3.00 mA. (a) What is the resistance of the resistor measured in ohms? (b) If the temperature of the resistor is increased to 60 °C by heating the resistor, what is the current through the resistor?
A long wire with a radius of 0.400 cm carries a current. The potential difference across a 3.60 m long section of this wire is 12.0 V, and the wire carries a current of 0.370 A. (a) What is the resistance (in Ω) of the 3.60 m long section of wire? Ω (b) What is the resistivity (in Ω · m) of the wire? Ω · m
A 4.5×10−4 V/m electric field creates a 2.0×1017 electrons/s current in a 1.6-mm-diameter aluminum wire. What is the drift speed? What is the mean time between collisions for electrons in this wire?
Q1: Upton Chuck is riding the Giant Drop at Great America. If Upton free falls for 2.60 seconds, what will be his final velocity and how far will he fall? Q2: A wire of length 3 m and area of cross-section 1.7 × 10-6 m2 has a resistance 3 × 10-2 ohm.a. What is the formula for resistivity of the wire and what is the unit of it?b. Calculate the resistivity of the wire.Q3: A point charge of −2 μC is located at the center of a cube with sides L=5 cm. What is the net electric flux through the surface?
An electric flat iron draws a current of 15 A when connected to a 110 V line. (a) Assuming that the heating element of the flat iron obeys Ohm's law, what is its resistance? (b) What is the resistivity of the heating element if it is a wire that is 2.5 cm long with a cross-sectional area of 2 x 10-4 m2 ?
An aluminum wire with a diameter of 0.100 mm has a uniform electric field of 0.200 V/m imposed along its entire length. The temperature of the wire is 50.0°C. Assume one free electron per atom. (a) Use the informa- tion in Table 27.2 and determine the resistivity. (b) What is the current density in the wire? (c) What is the total current in the wire? (d) What is the drift speed of the conduction electrons? (e) What potential difference must exist between the ends of a 2.00-m length of the wire to produce the stated electric field?