Physics: Introduce the knowledge of electrical circuits and electrical appliances in the home no le

First of all, a leakage protector must be installed before entering the house, and then all layers of indoor and various electrical appliances should be separated by monolithic circuit breakers, it should be noted that the load behind the monolithic circuit breaker should not be too large, if the load behind the monolithic circuit breaker is too large, it is best to divide it into several roads to reduce the load of the circuit breaker and line wires. Generally, the household lighting circuit breaker can choose 10A, the socket circuit breaker should be selected 16A, and the air conditioner and others should be selected according to the specific electrical appliances (generally 1 kilowatt with 5A is enough), if it is a factory or oh oh others, it should be considered according to the actual situation. The wire diameter of household lamps should generally not be less than square millimeters, and the load should not be greater than 2 kilowatts, the diameter of the socket wire should not be less than square millimeters, and the load should not be greater than 4 kilowatts, the air conditioner should be set off separately, the bathroom should be set off separately, and it should be noted that other lines that may exceed 2 kilowatts should also be set off separately.

In general, other lines other than electric lights must have reliable grounding, that is, the grounding wire must be installed. It should be noted that unless it is absolutely necessary, it is not a circuit, do not wear it into a pipe, that is, a circuit and pipe. Weak current lines should never be connected with strong current lines, because this will cause signal interference.

Okay, I'll start with that, I hope it helps you.

Only the voltmeter measures the physical quantities in the circuit, the same.

First of all, distinguish the connection mode of the circuit, and then look at the voltmeter to measure the voltage at both ends of the circuit, and solve it according to the law of the series and parallel circuit.

VoltammetryVoltammetry (also known as voltmeter, amperometer) is a more common method of measuring resistance, by using Ohm's law: r=u i to measure the value of resistance. Because it divides the voltage by the current, it is called voltammetry.

Use a voltmeter in parallel to measure the voltage at both ends of the resistor, and an ammeter in series to measure the current strength of the resistance through it. However, since the internal resistance of the meter often has an impact on the measurement results, this method often introduces significant systematic errors.

There are two types of connection: external and internal. The so-called external internal connection means that the ammeter is connected to the outside or inside of the voltmeter.

In this way, when connected to the outside, the current measured is the parallel connection of the voltmeter and the resistance, and the voltage value is accurate, and the current distribution when connected in parallel according to Ohm's law is inversely proportional to the resistance, and this connection method is suitable for measuring the resistance with a small resistance value; Connected inside, the ammeter is accurate, but the voltmeter measures the common voltage of the ammeter and the resistance, according to Ohm's law, the voltage distribution when connected in parallel is proportional to the resistance, this connection method is suitable for measuring the resistance of the larger resistance.

In addition, in order to eliminate the influence of voltmeter and ammeter, there are various compensation circuits for volt-ampere resistor, but all need to use an ammeter, and the circuit is very cumbersome.

Although the accuracy of voltammetry resistance measurement is not very high, the measuring instruments used are relatively simple and easy to use. It is the most basic method of measuring resistance, and there are many methods for measuring resistance, such as alternative method and Wheatstone bridge method.