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Author Question: A 1200 W hair dryer used for 10 minutes uses as much energy as a 1000 W hair dryer run 12 minutes. ... (Read 77 times)

CQXA

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on: Jul 28, 2018
A 1200 W hair dryer used for 10 minutes uses as much energy as a 1000 W hair dryer run 12 minutes.
 
  What will be an ideal response?

Question 2

Lighting is a place where lots of energy can be saved.
 
  What will be an ideal response?


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kingdude89

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Reply #1 on: Jul 28, 2018
Answer to Question 1

This is correct: the power of 1200 W in the first case used for 10 min (600 s),
giving an energy use PDt = (1200 W)(600 s) = 720,000 J. In the second case, the power is
1000 W but the time is 12 min (720 s), giving an energy use of PDt = (1000 W)(720 s) =
720,000 J, exactly the same.

Answer to Question 2

Lighting uses up to 7.5 of total energy use. Much energy (and money) can be
saved in lighting.


CQXA

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Reply #2 on: Jul 28, 2018
TY


kingdude89

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Reply #3 on: Jul 28, 2018
You're welcome


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