The brightness of 20W high efficiency energy-saving lamp is equivalent to 100W incandescent lamp. Four 100W incandescent lamps in a household all use this energy-saving lamp. If they are used for 5 hours a day on average, they can save electricity in 30 days______ It can save electricity______ 5 yuan / kW · h)

The brightness of 20W high efficiency energy-saving lamp is equivalent to 100W incandescent lamp. Four 100W incandescent lamps in a household all use this energy-saving lamp. If they are used for 5 hours a day on average, they can save electricity in 30 days______ It can save electricity______ 5 yuan / kW · h)

One hour energy saving △ w = (P1-P2) t = (0.1kw-0.02kw) × 1H = 0.08Kw · h, 4 animals use 5 hours a day, 30 days can save electricity w = 0.08Kw · h × 4 × 5 × 30 = 48kW · h, can save electricity 48kW · h × 0.5 yuan / kW · H = 24 yuan

The working hours of 220 V, 15 W incandescent lamp and 220 V, 15 energy-saving lamp are the same. Who consumes more power? Which one will be brighter

Both lamps are 15W, so the power consumption is the same. Energy saving lamps are relatively bright

The use of energy-saving lamps, energy-saving effect is obvious, generally 15 watts of energy-saving lamps produce brightness and 60-80 watts of ordinary incandescent lamps, but can save electricity_______ .
A.50%
B.66%
C.75%

c

How to accurately calculate the power consumption of household appliances and the size of air switch chosen?

There is no need to accurately calculate the power consumption of household appliances. Just make a general calculation and set aside a certain amount of added capacity. In general, 8 kW is enough for a family. 32-40a circuit breaker is selected for the switch and 6-10 square copper core is selected for the incoming line