Please design a circuit with LED as indicator light, the power supply is AC 220 V, and the electric appliance is optional Requirements: no matter whether the electrical appliances are working or not, as long as the power is turned on, the LED can emit light (that is, the LED is used as the indicator light of current input, not the indicator light of electrical appliances), and the circuit diagram and relevant parameters are given

Please design a circuit with LED as indicator light, the power supply is AC 220 V, and the electric appliance is optional Requirements: no matter whether the electrical appliances are working or not, as long as the power is turned on, the LED can emit light (that is, the LED is used as the indicator light of current input, not the indicator light of electrical appliances), and the circuit diagram and relevant parameters are given

The red LED is connected in series with 150k resistor and then connected to 220V

After the household electricity of 220 V turns into 24 V, the inverter can change back to 220 v. how can 24 V AC invert 220 V AC
My 24 V electricity is 220 V household electricity. I want to use inverter to change it back to 220 V household electricity. Besides inverter, what else do I need?

The 24 V DC is changed into 220 V 50 Hz AC by circuit pulse oscillation, high power transistor amplification, step-up transformer boost

Is it OK to change 12V inverter to 220V with car power?
I would like to use the car generated electricity (12V) on the 220 V 3000 w reverse electrical conversion into 220 V electricity can you?
In the case of battery power loss, can you continue to convert the car into 220 V when it is started?

We can get the voltage of 220 V, but the power is less than 3000 W, because if we want to get the power of 220 V and 3000 w with the voltage of 12 V, the current will reach more than 300 a (the efficiency can't reach 100%). The car battery is generally 65 ah, and the power will be discharged in a few minutes with the high current of 300 a (5C)! The power of the car generator is generally about 1 kW, and it won't reach 3000 w! Of course, If the power of the electric appliance is relatively small (below 500W), you can start the car in case of battery loss and continue to convert it into 220V

How many watts is suitable for the energy saving lamp in the bedroom?

This is related to the size of the room, furniture and wall color (light reflection)
Bedroom, use energy-saving lamp, it is 1 to 1.5 Watt per square metre commonly, add a lamp additionally (read a book to use)
Suggestion: incandescent lamp with 25 to 40 watts, energy saving lamp and incandescent lamp are 2700k or 3000K