The dial of an electric energy meter is marked with the word "3000r / kWh", which means that for every 1 kwh of electric energy consumed, the rotary table of electric energy turns 3000 circles. If only one bulb is connected in the room, and the rotary table turns 15R within 3 minutes, how many kWh and J are the electric energy consumed by the bulb during this period?

The dial of an electric energy meter is marked with the word "3000r / kWh", which means that for every 1 kwh of electric energy consumed, the rotary table of electric energy turns 3000 circles. If only one bulb is connected in the room, and the rotary table turns 15R within 3 minutes, how many kWh and J are the electric energy consumed by the bulb during this period?

15r/3000r=0.005KWh
The sixth power of 0.005 × 3.6 × 10 = 3600j

10A in "10 (20) a" on the rating plate of electric energy meter is the calibration current, and 20A is the rated maximum current. What is the difference between the calibration current and the rated current?

"10A" is the maximum current for continuous operation, "20A" is the maximum current for short time
The calibration current means that the meter can work stably for a long time in this current range, and the maximum current means that the meter can still work accurately in this current range, but it cannot work for a long time

If a meter is marked with 10a, then the rated current of the meter is 10a, right?

If a certain electric energy meter is marked with 10a, the rated current of the electric energy meter is 10A. The power supply voltage is 220 V, the power consumption is 2 kW, the power consumption is 380 V, and the power consumption is 4 kW. Overload cannot be too much. Less than a certain amount is OK