Monday

Period 1
How Lightning Works and Why Thunder Occurs

Uses of Static Electricity
Hazards of Static Electricity
Electrical Safety Devices
Electrical Power and Energy Efficiency:
Q 5-7 p. 535 (copied below)
Q 5 - Calculate the efficiency of a CFL if it produces 30J of light energy and uses 95J of electrical energy.
Q 6. Calculate the cost of operating the following devices. The cost of electricity is 12 c/kWh
a) a 100 W incandescent light bulb for 1000 hours
b) a 13 W CFL for 1000 hours
c) a 400W computer for 600 hours
d) a refridgerator operating at its peak power of 750W for one year
Q 7. Calculate the difference between the operating cost of a 60W incandescent light bulb and a 13 W CFL each operating 100 hours. The cost of electricity is 11c/kWh.
HMK
Any of the above Q's not done in class
Research and record how 2 of the items listed in the note operate using static electricity
TEST WEDNESDAY

Answers to Ohms Law Questions (remember you must include the correct units for a correct answer)
1. 800 ohms
2. 300 V
3. 3 A
4. 48 ohms
5. 22 ohms
6. 63 V
7. 60 A
8. 100 ohms
9. 6 A
10. 10.9 A
11. (left to right) 40 ohms, 1.5 A, 80 ohms, 90 ohms, 10 V, 3 A, 30 V, 10 V, 4.3 ohms, 0. 25 A

Answers to Static Electricity Practice Questions:
1. D
2. B
3. C
4. B
5. A
6. B
7. A
8. C
9. D
10. C
11. A
12. B
13. C
14. B
15. A
16. B
17. D
18. B
19. D
20. B
21. D
22. Air is more humid in the summer than winter. When air is humid it contains more water which transfers electric charge. Thus in winter without the humidity, the air does not reduce/take away the charge and the charge remains on the object and builds.
23. The laser "draws" the image on the drum making the area to be printed/copied negatively charged (figure a). The drums rolls across the positively charged toner which attracts the negatively charged laser "drawing" (figure b). Then the drum rolls across the paper with a higher negative charge and the toner particles stick to the paper (figure c)
24. When 2 neutral objects come into contact with one another electrons can be transferred from one object to the other (charging by friction). The rubber on the balloon becomes negative and the hair becomes positive (electrostatic series). Opposites attract which is why the balloon sticks to the hair.

Period 3 - see above if you missed the answers to the practice static review questions
Notes - topics see Period 1
Practice Q's - see pictures Period 1
Completion of News Report - due Thursday
HMK
Same Q's as Period 1 Q 5-7 p. 535 - see Period 1 for Q's (I typed them out on the blog so you don't require the text)
News Report due Thursday if not done today in class (must have rough copy edited by 2 people, good copy and rubric)
TEST WEDNESDAY

Period 4
Completion of Soil profiles, posters (were for homework last week and due today)
Letters to New Canadians
Definition of Ecozones

Ecozone Map - colour and complete legend
HMK
Any of the above not completed in class