Question

Ceiling-mounted fluorescent lighting fixtures with total power equal to 400 W are used to produce an average illumination level of 600 lux on student desks in a particular classroom. If the classroom lights are on 10 hours a day for 200 days per year, calculate the annual energy used for lighting in this classroom.

A 800 kWh
B 2 kWh
C 2,000 Wh
D 2,000 kWh
E 800,000 kWh
F 600 kWh

Answer 1

`E = 800\,kWh`

Step-by-step explanation:

The annual energy used for lighting in the classroom is:

`E = (0.4\,kW)\cdot \left(10\,(h)/(day) \right)\cdot \left(200\,(day)/(year) \right) \cdot \left(1\,(kWh)/(year) \right)`

`E = 800\,kWh`