Transcript Review Question Ch 22 Test

Review Question Ch 22 Test
1. Watt is the SI unit for power?
ans: Watt
2. The rate at which a charge moves in a
wire is called:
ans: current
3. What is the unit for electrical potential?
ans: joule
4. As a charge in an electric field moves
away from the source, the PE electric will
ans: decrease
5. What is the equation to define current?
ans: I = DQ/Dt
6. What is the SI unit for current?
ans ampere (A)
7. What does one ampere equal?
ans: 1 C/s
8. What is the electric potential when a
charge of 6.5 x 1014 J set 2 cm in a
uniform electric field of 345 N/C?
ans: 4.5 x 1015 J
9. A current runs at 0.025 A through a
conductor. How long will it take fro a total
charge of 4.5 C to pass?
ans: 180 s
10. As the length of a conductor increases,
the resistance will:
ans: increase
11. As the temperature of a conductor
increase, the current will:
ans: decrease
12. The larger the cross-sectional surface
area, the ____ the resistance.
ans: less
13. The ratio between the potential difference
and the current is called:
ans: resistance
14. What is the SI unit for resistance?
ans: ohm
15. What is critical temperature?
ans: below that temp resistance is zero
16. What is the equation to define current?
ans: I = DV/R
17. A circuit has a current of 6 A from 110 V.
What is the resistance?
ans: 18.3 ohm’s
18. A TV operates with 120 V , 20 W. What is
the current?
ans: 6 A
19. What is the unit equivalence of the watt?
ans: J/s
20. A hair dryer draws a current of 9.1 A.
a. How long does it take for 1.9 x 103 C to
pass through the hairdryer?
ans: 208.8 s
b. How many electron is this time?
ans: 1.2 x 1022 e21. A 9 V battery has a current of 1.5 A. What
is the resistance?
ans: 6 ohm’s
22. Two charged bodies equal to 2.5 x 1024
electrons each having an electric potential
of 5.5 x 10-19 J. What is the distance?
ans: 2.6 x 1039 m
23. The smaller the # gauge, the larger the
cross-sectional surface area. Which has
greater resistance, 16-gauge or 8-gauge?
ans: 16-gauge, smallest area
24. A 800 W oven runs off a 220 V circuit.
What is the resistance? What is the cost to
cook a turkey for 4 hrs at $ 0.086 kW h?