Download Ch 18: Electric Current Study Guide

Name: ______________
Ch 18: Electric Current
Study Guide
Vocabulary matching: Match each vocabulary term from the word bank below to the
appropriate definition.
electrons
Ampere (A)
ammeter
current
1.
lower
Ohm
current
higher
batteries
directly
temperature
electric
resistance
energy
amperes
parallel
Potential difference
______________ Electric currents transfer ___ from one place to another.
2. ______________ Electrons flow from ____ to ___ potential.
3. ______________ ____ and generators are devices that pump electrons to an object with a higher
concentration of electrons than the original object.
4. ______________ Electric current is measured in ____.
5. ______________ Electron pumps convert various forms of energy to ____ energy.
6. ______________ A current flow of one coulomb per second is one ___.
7. ______________ _____ discovered that the ratio of the potential difference between the ends of a
wire and the current flowing through the wire is a constant.
8. ______________ The current that flows through a wire varies ____ as the applied voltage
9. ______________ The ohm is a unit of electric ____.
10. ______________ A voltmeter should be connected in ____ with the resistance in a circuit.
11. ______________ A(n) ___ measures the current flowing in a circuit.
12. ______________ Electric power is found by multiplying _____ by current.
13. ______________ The power used by a resistor is directly proportional to its resistance and to the
square of the ____ through the resistor.
14. ______________ In many materials, resistance increases when ____ rises.
15. ______________ The kilowatt hour is a unit for measuring ___.
16. ______________ The thermal energy produced in a circuit from electric energy varies directly with
the resistance, the time interval, and the square of the ____.
17. A 4.0 Ω resistor is connected to a 6.0 V battery. What is the current?
18. An iron is rated at 1680 W and is connected to a 120.0 V outlet. Calculate the current that the
iron draws.
19. A 60.0 W light bulb is connected to a 120.0 V outlet. What is the resistance of the bulb?
20. A car battery causes a current of 2.0 A through a lamp that produces 12 V across it. What is the
power used by the lamp?
21. A motor with an operating resistance of 32 Ω is connected to a voltage source. The current in the
circuit is 3.8 A. What is the voltage of the source?
22. A current of 1.82 A flows through a copper wire 1.75 m long and 1.10 mm in diameter. Find the
potential difference between the ends of the wire.