Physics
Grade-9
Easy
Question
An electrician installs patio lights in a back yard. Which of the following will decrease the efficiency of the wiring system to the back yard?
1- Bury the extension cord very deep down underground.
2- Use a short extension cord.
3- Use a long extension cord.
4- Use compact fluorescent light bulbs
- 1 and 2
- 1 and 3
- 2 and 4
- 3 and 4
Hint:
1 and 3
The correct answer is: 1 and 3
It is never advisable and it is not designed to bury extension cord deep under the ground .
Using long extension cord can affect efficiency as it has resistance. So, more length will lead to more resistance.
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