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Author Question: The approximate daily energy consumption of primitive humans (before fire) was about a. 2000 ... (Read 12 times)

skymedlock

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The approximate daily energy consumption of primitive humans (before fire) was about
 
  a. 2000 kilojoules.
  b. 8000 kilojoules.
  c. 12,000 kilojoules.
  d. 48,000 kilojoules
  e. 400,000 kilojoules.

Question 2

A stay-at-home mom watches soap operas for 1.5 h each day and her husband vegges out in front of the tube for around 2 h a night.
 
  He also watches the football games on Saturday and Sunday during football season (two games each day, 6 hours of watching). How much does this family pay to watch TV every year? Assume the cost of electricity is 0.08/kWh.



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bblaney

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Answer to Question 1

B

Answer to Question 2

We assume from the description that this is the weekday ritualwatching the TV
for a total time of 3.5 h. From Table 8.7, we use 200 W as the power drawn by the TV. So,
we find 5 d x 3.5 h/d x 200 W = 3500 Wh = 3.5 kWh. Weekend watching totals 12 h, so
energy use from the weekend totals 200 W x 12 h = 2400 Wh = 2.4 kWh. Total weekly
energy use is 5.9 kWh. The cost is 5.9 kWh x 0.08/kWh = 0.47.




skymedlock

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Reply 2 on: Jul 28, 2018
Excellent


tkempin

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Reply 3 on: Yesterday
Great answer, keep it coming :)

 

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