There are 10 "220 V, 40 V" electric lamps and 4 "220 V, 100 W" electric fans in the classroom. Question: 1. What is the total power when all the electrical appliances are working normally? 2. If you work 6 hours a day, how much kw'h of electric energy is consumed in a month (30 days)

1、40×10+100×4=800W
2. 800W = 0.8kw, power consumption in one month is 0.8 × 6 × 30 = 144kwh

The TV set and electric blanket marked with 220 V / 100 W work normally for 1 hour. Which electric appliance gives out more heat? Why?

Electric blanket, because electric blanket converts all electric energy into internal energy, while TV mainly converts electric energy into light energy and sound energy

The rated power of an electric fan is 100W, and the internal resistance is 2 Ω. When it is connected to the power supply of 220V, it can work normally
(1) When the electric fan works normally, how much current is passing through it? How much electrical energy is converted into mechanical energy per second?
(2) If the electric fan doesn't work due to the fault when it is connected to the 220 V power supply, what is the current passing through the electric fan? What is its actual power?

(1)、P=IU
I=P/U=100/220=0.46
Thermal power P = I ^ 2R = 0.42
How much electrical energy is converted into mechanical energy per second 100-0.42 = 99.58
(2).I=U/r=110A
P=UI=220x110=24200

The ammeter of Xiaoming's house is marked with the words of 220V 10A. His house has 5 40W electric lamps and 1 100W TV set
One 140 watt refrigerator, one 700 w electric water heater and one 700 w electric rice cooker. Can these electric appliances be used at the same time?

Hello
First, we need to calculate the rated power, P = IU = 220 * 10 = 2200W
So the total power of the electric appliance is 40 * 5 + 100 + 140 + 700 + 700 = 1840w < 2200W
Therefore, it can be used at the same time
Welcome to adopt

There are 10 "220 V, 40 V" electric lamps and 4 "220 V, 100 W" electric fans in the classroom. Question: 1. What is the total power when all the electrical appliances are working normally? 2. If you work 6 hours a day, how much kw'h of electric energy is consumed in a month (30 days)