Physics voltmeter question

2008-03-27 5:11 pm

Q1)3 light bulbb connected in series to a 30V supply.What is the voltage across ecah lamp?
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▏' =Dry cell

○=light bulb▏

Q2) 3 light bulb connect in parallel to a 30V supply.What is the voltage across ecah lamp?

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Q3)Light bulb 1 connect parallel with Light bulb 2,3,4.
Light bulb 2,3,4 connect in series.
The voltage of dry cell is 60V.
Find out the voltage across light 1,2,3,4

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回答 (1)

用戶179770

2008-03-27 5:31 pm

✔ 最佳答案

1. 10V for each
2. 30V for each
3. 60V for bulb 1 and 20V for each of the remaining three bulbs

For an exam-oriented approach*, you can view the bulbs in series as "sharing" the voltage of the battery, so when 3 bulbs are connected in series, they equally share the 30V, so each of them consumes 10V. However, when bulbs are connected in parallel, each branch will consume the voltage supplied by batteries, hence each branch will have 60V in Q3 and 30V in Q2.

*Frankly it's not somehow a correct physics concept, but it'll be the easiest way of grabbing the idea for exam use.

參考: My ownself.

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