Electronic devices use electrical energy even when they are on standby.Calculate the percent of energy used per day for the following entertainment equipment in the standby mode assuming that they are plugged in all the time.
A)0.45%
B)1.1%
C)4.8%
D)5.1%
E)None of these is correct.

Question

Electronic devices use electrical energy even when they are on standby.Calculate the percent of energy used per day for the following entertainment equipment in the standby mode assuming that they are plugged in all the time. 
A)0.45% 
B)1.1% 
C)4.8% 
D)5.1% 
E)None of these is correct.

Quizplus · Accepted Answer

The percent of energy used per day in standby mode can be calculated as follows:
- DVD player: 0.86 watts x 24 hours = 20.64 watt-hours per day
- TV: 7.3 watts x 24 hours = 175.2 watt-hours per day
- Sound system: 2.2 watts x 24 hours = 52.8 watt-hours per day
- Total energy used per day = 20.64 + 175.2 + 52.8 = 248.64 watt-hours per day
- Percent of energy used per day = (248.64 watt-hours / 5,000 watt-hours per month) x 100% = 4.97%
Therefore, the closest option is C) 4.8%.

Electronic Devices Use Electrical Energy Even When They Are on Standby.Calculate