1 Units, Physical Quantities, And Vectors 2 Motion Along A Straight Line 3 Motion In Two Or Three Dimensions 4 Newton’s Laws Of Motion 5 Applying Newton’s Laws 6 Work And Kinetic Energy 7 Potential Energy And Energy Conservation 8 Momentum, Impulse, And Collisions 9 Rotation Of Rigid Bodies 10 Dynamics Of Rotational Motion 11 Equilibrium And Elasticity 12 Fluid Mechanics 13 Gravitation 14 Periodic Motion 15 Mechanical Waves 16 Sound And Hearing 17 Temperature And Heat 18 Thermal Properties Of Matter 19 The First Law Of Thermodynamics 20 The Second Law Of Thermodynamics 21 Electric Charge And Electric Field 22 Gauss’s Law 23 Electric Potential 24 Capacitance And Dielectrics 25 Current, Resistance, And Electromotive Force 26 Direct-current Circuits 27 Magnetic Field And Magnetic Forces 28 Sources Of Magnetic Field 29 Electromagnetic Induction 30 Inductance 31 Alternating Current 32 Electromagnetic Waves 33 The Nature And Propagation Of Light 34 Geometric Optics 35 Interference 36 Diffraction 37 Relativity 38 Photons: Light Waves Behaving As Particles 39 Particles Behaving As Waves 40 Quantum Mechanics I: Wave Functions 41 Quantum Mechanics Ii: Atomic Structure 42 Molecules And Condensed Matter 43 Nuclear Physics 44 Particle Physics And Cosmology expand_more
25.1 Current 25.2 Resistivity 25.3 Resistance 25.4 Electromotive Force And Circuits 25.5 Energy And Power In Electric Circuits 25.6 Theory Of Metallic Conduction Chapter Questions expand_more
Problem 25.1DQ: The definition of resistivity ( = E/J) implies that an electric field exists inside a conductor. Yet... Problem 25.2DQ: A cylindrical rod has resistance R. If we triple its length and diameter, what is its resistance, in... Problem 25.3DQ: A cylindrical rod has resistivity . If we triple its length and diameter, what is its resistivity,... Problem 25.4DQ: Two copper wires with different diameters are joined end to end. If a current flows in the wire... Problem 25.5DQ: When is a 1.5-V AAA battery not actually a 1.5-V battery? That is, when do its terminals provide a... Problem 25.6DQ: Can the potential difference between the terminals of a battery ever be opposite in direction to the... Problem 25.7DQ: A rule of thumb used to determine the internal resistance of a source is that it is the open-circuit... Problem 25.8DQ: Batteries are always labeled with their emf; for instance, an AA flashlight battery is labeled 1.5... Problem 25.9DQ: We have seen that a coulomb is an enormous amount of charge; it is virtually impossible to place a... Problem 25.10DQ: Electrons in an electric circuit pass through a resistor. The wire on either side of the resistor... Problem 25.11DQ: Temperature coefficients of resistivity are given in Table 25.2. (a) If a copper heating element is... Problem 25.12DQ: Which of the graphs in Fig. Q25.12 best illustrates the current I in a real resistor as a function... Problem 25.13DQ: Why does an electric light bulb nearly always burn out just as you turn on the light, almost never... Problem 25.14DQ: A light bulb glows because it has resistance. The brightness of a light bulb increases with the... Problem 25.15DQ: (See Discussion Question Q25.14.) An ideal ammeter A is placed in a circuit with a battery and a... Problem 25.16DQ: (See Discussion Question Q25.14.) Will a light bulb glow more brightly when it is connected to a... Problem 25.17DQ: The energy that can be extracted from a storage battery is always less than the energy that goes... Problem 25.18DQ: Eight flashlight batteries in series have an cmf of about 12 V, similar to that of a car battery.... Problem 25.19DQ: Small aircraft often have 24-V electrical systems rather than the 12-V systems in automobiles, even... Problem 25.20DQ: Long-distance, electric-power, transmission lines always operate at very high voltage, sometimes as... Problem 25.21DQ: Ordinary household electric lines in North America usually operate at 120 V. Why is this a desirable... Problem 25.22DQ: A fuse is a device designed to break a circuit, usually by melting when the current exceeds a... Problem 25.23DQ: High-voltage power supplies are sometimes designed intentionally to have rather large internal... Problem 25.24DQ: The text states that good thermal conductors are also good electrical conductors. If so, why dont... Problem 25.1E: Lightning Strikes. During lightning strikes from a cloud to the ground, currents as high as 25,000 A... Problem 25.2E: A silver wire 2.6 mm in diameter transfers a charge of 420 C in 80 min. Silver contains 5.8 1028... Problem 25.3E: A 5.00-A current runs through a 12-gauge copper wire (diameter 2.05 mm) and through a light bulb.... Problem 25.4E: An 18-gauge copper wire (diameter 1.02 mm) carries a current with a current density of 3.20 106... Problem 25.5E: Copper has 8.5 1028 free electrons per cubic meter. A 71.0-cm length of 12-gauge copper wire that... Problem 25.6E Problem 25.7E: CALC The current in a wire varies with time according to the relationship I = 55 A (0.65 A/s2)t2.... Problem 25.8E: Current passes through a solution of sodium chloride. In 1.00 s, 2.68 1016 Na+ ions arrive at the... Problem 25.9E: BIO Transmission of Nerve Impulses. Nerve cells transmit electric signals through their long tubular... Problem 25.10E: (a) At room temperature, what is the strength of the electric field in a 12-gauge copper wire... Problem 25.11E: A 1.50-m cylindrical rod of diameter 0.500 cm is connected to a power supply that maintains a... Problem 25.12E: A copper wire has a square cross section 2.3 mm on a side. The wire is 4.0 m long and carries a... Problem 25.13E Problem 25.14E Problem 25.15E: A cylindrical tungsten filament 15.0 cm long with a diameter of 1.00 mm is to the used in a machine... Problem 25.16E: A ductile metal wire has resistance R. What will be the resistance of this wire in terms of R if it... Problem 25.17E Problem 25.18E Problem 25.19E Problem 25.20E Problem 25.21E: A current-carrying gold wire has diameter 0.84 mm. The electric field in the wire is 0.49 V/m. What... Problem 25.22E: A hollow aluminum cylinder is 2.50 m long and has an inner radius of 2.75 cm and an outer radius of... Problem 25.23E Problem 25.24E: A carbon resistor is to be used as a thermometer. On a winter day when the temperature is 4.0C, the... Problem 25.25E: A copper transmission cable 100 km long and 10.0 cm in diameter carries a current of 125 A. (a) What... Problem 25.26E: Consider the circuit shown in Fig. E25.26. The terminal voltage of the 24.0-V battery is 21.2 V.... Problem 25.27E: An ideal voltmeter V is connected to a 2.0-11 resistor and a battery with emf 5.0 V and internal... Problem 25.28E: An idealized ammeter is connected to a battery as shown in Fig. E25.28. Find (a) the reading of the... Problem 25.29E: When switch S in Fig. E25.29 is open, the voltmeter V reads 3.08 V. When the switch is closed, the... Problem 25.30E: The circuit shown in Fig. E25.30 contains two batteries, each with an emf and an internal... Problem 25.31E: In the circuit shown in Fig. E25.30, the 16.0-V battery is removed and reinserted with the opposite... Problem 25.32E: In the circuit of Fig. E25.30, the 5.0- resistor is removed and replaced by a resistor of unknown... Problem 25.33E: The circuit shown in Fig. E25.33 contains two batteries, each with an emf and an internal... Problem 25.34E: When a resistor with resistance R is connected to a 1.50-V flashlight battery, the resistor consumes... Problem 25.35E: Light Bulbs. The power rating of a light bulb (such as a 100-W bulb) is the power it dissipates when... Problem 25.36E: If a 75-W" bulb (see Problem 25.35) is connected across a 220-V potential difference (as is used in... Problem 25.37E: European Light Bulb. In Europe the standard voltage in homes is 220 V instead of the 120 V used in... Problem 25.38E: A battery-powered global positioning system (GPS) receiver operating on 9.0 V draws a current of... Problem 25.39E: Consider the circuit of Fig. E25.30. (a) What is the total rate at which electrical energy is... Problem 25.40E: BIO Electric Eels. Electric eels generate electric pulses along their skin that can be used to stun... Problem 25.41E: BIO Treatment of Heart Failure. A heart defibrillator is used to enable the heart to start beating... Problem 25.42E: The battery for a certain cell phone is rated at 3.70 V. According to the manufacturer it can... Problem 25.43E Problem 25.44E: An idealized voltmeter is connected across the terminals of a 15.0-V battery, and a 75.0- appliance... Problem 25.45E: A 25.0- bulb is connected across the terminals of a 12.0-V battery having 3.50 ft of internal... Problem 25.46E: A typical small flashlight contains two batteries, each having an emf of 1.5 V, connected in series... Problem 25.47E: In the circuit in Fig. E25.47, find (a) the rate of conversion of internal (chemical) energy to... Problem 25.48E: A 540-W electric heater is designed to operate from 120-V lines, (a) What is its operating... Problem 25.49E Problem 25.50P: In an ionic solution, a current consists of Ca2+ ions (of charge +2e) and Cl ions (of charge e)... Problem 25.51P: An electrical conductor designed to carry large currents has a circular cross section 2.50 mm in... Problem 25.52P: An overhead transmission cable for electrical power is 2000 m long and consists of two parallel... Problem 25.53P: On your first day at work as an electrical technician, you are asked to determine the resistance per... Problem 25.54P: A 2.0-m length of wire is made by welding the end of a 120-cm-long silver wire to the end of an... Problem 25.55P: A 3.00-m length of copper wire at 20 C has a 1.20-m long section with diameter 1.60 mm and a... Problem 25.56P: A heating clement made of tungsten wire is connected to a large battery that has negligible internal... Problem 25.57P: CP BIO Struck by Lightning. Lightning strikes can involve currents as high as 25,000 A that last for... Problem 25.58P: A resistor with resistance R is connected to a battery that has emf 12.0 V and internal resistance r... Problem 25.59P: CALC A material of resistivity is formed into a solid, truncated cone of height h and radii r1 and... Problem 25.60P: CALC The region between two concentric conducting spheres with radii a and b is filled with a... Problem 25.61P: The potential difference across the terminals of a battery is 8.40 V when there is a current of 1.50... Problem 25.62P: (a) What is the potential difference Vad in the circuit of Fig. P25.62? (b) What is the terminal... Problem 25.63P: BIO The average bulk resistivity of the human body (apart from surface resistance of the skin) is... Problem 25.64P: BIO A person with body resistance between his hands of 10 k accidentally grasps the terminals of a... Problem 25.65P: A typical cost for electrical power is 0,120 per kilowatt-hour. (a) Some people leave their porch... Problem 25.66P: In the circuit shown in Fig. P25.66, R is a variable resistor whose value ranges from 0 to , and a... Problem 25.67P: A Nonideal Ammeter. Unlike the idealized ammeter described in Section 25.4, any real ammeter has a... Problem 25.68P: A cylindrical copper cable 1.50 km long is connected across a 220.0-V potential difference, (a) What... Problem 25.69P: CALC A 1.50-m cylinder of radius 1.10 cm is made of a complicated mixture of materials. Its... Problem 25.70P: Compact Fluorescent Bulbs. Compact fluorescent bulbs are much more efficient at producing light than... Problem 25.71P Problem 25.72P: CP Consider the circuit shown in Fig. P25.72. The battery has emf 72.0 V and negligible internal... Problem 25.73P: CP Consider the circuit shown in Fig. P25.73. The emf source has negligible internal resistance. The... Problem 25.74P: DATA An external resistor R is connected between the terminals of a battery. The value of R varies.... Problem 25.75P: DATA The voltage drop Vab across each of resistors A and B was measured as a function of the current... Problem 25.76P: DATA According to the U.S. National Electrical Code, copper wire used for interior wiring of houses,... Problem 25.77CP Problem 25.78CP: An external resistor with resistance R is connected to a battery that has emf and internal... Problem 25.79PP: BIO SPIDERWEB CONDUCTIVITY. Some types of spiders build webs that consist of threads made of dry... Problem 25.80PP: BIO SPIDERWEB CONDUCTIVITY. Some types of spiders build webs that consist of threads made of dry... Problem 25.81PP: BIO SPIDERWEB CONDUCTIVITY. Some types of spiders build webs that consist of threads made of dry... Problem 25.82PP: BIO SPIDERWEB CONDUCTIVITY. Some types of spiders build webs that consist of threads made of dry... format_list_bulleted