Question

Question #5c599

Answer 1

Energy is power x time, or `E=pxxt`

Explanation:

To get the energy in kWh, we need to express the power in kW:

`p=4xx100W=400W=0.4kW` (remember `1kW=1000W`)

If all this is used for 10 hours a day, and september has 30 days, then the time factor is:

`t=10hxx30=300h`

Putting these together we get:

`E=pxxt=0.4kWxx300h=120kWh`