1. 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

2. 5. What is the equation to define current? ans: I =  Q/  t 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 10 14 J set 2 cm in a uniform electric field of 345 N/C? ans: 4.5 x 10 15 J

3. 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

4. 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

5. 16. What is the equation to define current? ans: I =  V/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 . What is the current? ans: 6 A 19. What is the unit equivalence of the watt? ans: J/s

6. 20. A hair dryer draws a current of 9.1 A. a. How long does it take for 1.9 x 10 3 C to pass through the hairdryer? ans: 208.8 s b. How many electron is this time? ans: 1.2 x 10 22 e- 21. A 9 V battery has a current of 1.5 A. What is the resistance? ans: 6 ohm’s

7. 22. Two charged bodies equal to 2.5 x 10 24 electrons each having an electric potential of 5.5 x 10 -19 J. What is the distance? ans: 2.6 x 10 39 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?