Chapter 23

5. Name two kinds of practical "electric pumps."

Generators or Chemical Batteries

15. Does a battery produce dc or ac? Does the generator at a power station produce dc or ac?

a battery produces DC a generator produces AC

21. What is meant by drift velocity?

the net flow of electrons along a wire

8. Will water flow more easily through a wide pipe or a narrow pipe? Will current flow more easily through a thick wire or a thin wire?

water flows more easily through a wide pipe, and current flows more easily through a thick wire.

27. Which of these is a unit of power and which is a unit of energy: a watt, a kilowatt, a kilowatt-hour?

watts and kilowatts are power kilowatt-hour is energy (bc energy=power•time)

29. In a circuit of two lamps in series, if the current through one lamp is 1 A, what is the current through the other lamp? Defend your answer.

1 ampere. the same current flows through lamps in a series Kirchoff's current rule in a series circuit

4. What exactly is an ampere?

1 coulomb/second and 1 coulomb = the charge of 6.25x10^18 electrons therefore 1 ampere=(the charge of 6.25x10^18 e-)/sec

30. If a voltage of 6 V is impressed across the circuit in the preceding question and the voltage across the first lamp is 2 V, what is the voltage across the second lamp? Defend your answer.

4 volts. The sum of the voltages across each lamp must add up to the total voltage across both lamps.

31. In a circuit of two lamps in parallel, if there is a voltage of 6 V across one lamp, what is the voltage across the other lamp?

6V, the total voltage is equal to the voltage of the first lamp is equal to the second lamp Vt=V1=V2=V3...

33. What is the function of fuses or circuit breakers in a circuit?

A fuse or a circuit breaker prevents overloading that may lead to fire.

32. How does the sum of the currents through the branches of a simple parallel circuit compare with the current in the voltage source?

The sum of the currents through the branches of a simple parallel circuit is equal to the current that flows through the voltage source.

2. What condition is necessary for the sustained flow of water in a pipe? What analogous condition is necessary for the sustained flow of charge in a wire?

a continuous difference in water levels is sustained with a suitable pump a sustained current requires a suitable pumping device to provide a difference in electric potential—a voltage."

19. What is the error in saying that electrons in a common battery-driven circuit travel at about the speed of light?

an electric field travels at the speed of light, not electrons

1. What condition is necessary for the flow of heat? What analogous condition is necessary for the flow of charge?

difference in temperature must be present for flow of heat potential difference must be present for flow of charges

26. What is the relationship among electric power, current, and voltage?

electric power is equal to the product of current and voltage. electric power = current x voltage

24. When you make your household electric payment at the end of the month, which are you billed for: voltage, current, power, or energy?

energy (but i feel like this is a trick question)

9. Does heating a metal wire increase or decrease its electrical resistance?

for most conductors, increasing temperature increases resistance

28. How does the heat emitted by lamps affect their efficiency?

heat emitted by lamps reduces their efficiency

14. What is the function of the round third prong in a modern household electrical plug?

it is a grounding wire. any charge built up on the appliance is conducted to the ground, preventing accidental shock

20. Why does a wire that carries electric current become hot?

moving electrons collide with metallic ions and transfer kinetic energy to them, creating hot current-carrying wires

10. What is the unit of electrical resistance?

ohm (Ω)

3. Why are electrons, rather than protons, the principal charge carriers in metal wires?

protons are bound inside of the nucleus, whereas one or more electrons from the conducting metals are free to move

11. If the voltage impressed across a circuit is held constant while the resistance doubles, what change occurs in the current?

the current is cut in half

12. If the resistance of a circuit remains constant while the voltage across the circuit decreases to half its former value, what change occurs in the current?

the current is cut in half

25. From where do the electrons originate that produce an electric shock when you touch a charged conductor?

the electrons that make up the current originate in your body (energy is what passes through the charged conductor to your body and shocks you, not electrons themselves.)