The electricity meter of a classmate's home is marked with 220V, 10a and 3000r/ The electric energy meter is marked with "220V 10A" and "3000r / kWh", which indicates that the electric energy meter can be connected to the electric appliances with a total power of () W at most. One day, all the electric appliances in the student's home (with a total power of 600W) work for 4h, then the dial of the electric energy meter will rotate ()? The second question needs process. The first question is I will, train of thought or process,

The electricity meter of a classmate's home is marked with 220V, 10a and 3000r/ The electric energy meter is marked with "220V 10A" and "3000r / kWh", which indicates that the electric energy meter can be connected to the electric appliances with a total power of () W at most. One day, all the electric appliances in the student's home (with a total power of 600W) work for 4h, then the dial of the electric energy meter will rotate ()? The second question needs process. The first question is I will, train of thought or process,

The student's family all uses electrical appliances to work for 4h, and the power consumption is as follows:
W=P't=0.6W×4h=2.4kW•h．
"3000r / kW &; H" for every 1kW &; h of electric energy consumed, the turntable of electric energy meter turns 3000r
Therefore, the circuit consumes 2.4kw &; h electric energy, and the number of turns of the electric energy meter turntable is 2.4 × 3000r = 7200r

The voltmeter has 220V, 5A, 3000r / kW * h. When the household appliance is working, the total power of the household appliance is 45r
When the household appliances work, the total power of the household appliances is 45r, the total working current of all the appliances does not exceed the electric energy, the total working current of all the appliances does not exceed the rated current of the meter, how many watts of appliances should be added.

The watt hour meter (not voltmeter) has "220 V, 5A, 3000 R / kW * H", which means that every kilowatt hour of electricity corresponds to 3000 revolutions
So when the electric energy meter turns 45, the total electric energy is e = (45 / 3000) kwh = 0.015 kwh = 0.015 kwh = 54000 joules
Note: due to insufficient conditions, other quantities cannot be calculated

If an electric water heater is used alone, the meter turntable turns 210 revolutions in 300s, how many kilowatt hours does the water heater consume in this process
This is a household electric energy meter marked with "3000r / kW"

You can take a look at the pulse constant of the meter, such as 1600imp / kW. H, which means 1600 rpm is a kilowatt hour, 210 RPM / 1600 is your kilowatt hour