On the issue of short circuits and open circuits of light bulbs.

There are two reasons why the bulb does not light up: it may be that the circuit where the bulb is located is broken, or that the bulb may be short-circuited (the two ends of the bulb are directly connected).

Bulb open circuit and short circuit have something in common: the bulb has no current, and neither bulb can work.

Difference: When the bulb is disconnected, there is voltage at both ends of the bulb.

There is no current in the entire circuit of the series circuit. In parallel circuits, there is no current in the branch where the open lamp is located.

When the bulb is short-circuited, the voltage across the bulb is 0. There is an external current at both ends of the bulb.

Series circuit, short circuit of the lamp that does not light up (local short circuit).

Parallel circuits, when the lamp is short-circuited (power short-circuit), dangerous.

In the example below, it is known that the bulb is open or short-circuited.

1. The ammeter is connected in series with the bulb L1 and L2, and the voltmeter measures the voltage of the L1 lamp. Close the switch, both lights are not on, the ammeter has no indicator, and the voltmeter has a large indicator. Which light is malfunctioning?

2. The ammeter is connected in series with the bulb L1 and L2, and the voltmeter measures the voltage of the L1 lamp. Close the switch, the L2 light is not on, the ammeter has an indicator, and the voltmeter has a large indicator. Which light is malfunctioning?

If the short circuit cannot be measured, it will be burned out, and the voltage measured by the voltage is the power supply voltage at both ends of the bulb.

If this one bulb or several small lamps run in series, the ammeter will burn out when measuring the current, and the voltage can be measured as the power supply voltage.

If it is several bulbs in series, the voltage and current are fine, and if the voltage is 0, the current is needless to say.

Two types: short circuit, partial short circuit.

In the power system, the so-called "short circuit" refers to the connection between phases or between phases (or neutral wires) outside the normal operation of the power system. The basic forms of short circuit in the three-phase system are: three-phase short circuit, two-phase short circuit, single-phase grounding short circuit, two-phase grounding short circuit.

An abnormal connection (i.e., short circuit) occurs between phases or between phases (or neutrals), sometimes when a very large current flows.

The current value is much greater than the rated current and depends on the electrical distance from the power supply at the short-circuit point. A short circuit is a low-resistance short circuit between conductive parts of different potentials, which is equivalent to a closed circuit directly connected by the wire without passing through the load. (Usually this is a serious and should be avoided as much as possible in the fault of the circuit, which will cause the circuit to burn out due to excessive current and cause a fire).

The power supply is short-circuited. That is, the current does not pass through any electrical appliance, but flows directly from the positive electrode back to the negative electrode through the wire. It is particularly easy to burn out the power supply.

Because the internal resistance of the power supply RO is small, the short-circuit current is large, and the terminal voltage of the power supply is 0, and the electromotive force of the power supply is all reduced to the internal resistance. Short-circuit current may cause mechanical and thermal damage or damage to the power supply, and the electrical energy generated by the power supply during the short circuit is all consumed by the internal resistance, and the short circuit is usually a serious accident and should be prevented as much as possible.

1. The bulb has a certain resistance, and there is also a rated voltage and current, you can directly observe it when you buy, and the number will be marked on the bulb, if there is a short circuit, it is equivalent to connecting the wires at both ends of the bulb, so that the voltage at both ends is equal to the power supply voltage, and the resistance is close to infinitesimus. According to Ohm's law, this current will be infinitely large, and if it exceeds the rated current, it is prone to the problem of short circuit, and to put it bluntly, it will be burned.

2. In addition, the bulb has two wires, one is the neutral line and the other is the live wire, if the two are connected together, it is also easy to short-circuit.

China Weather Network News Today (November 23) at 6 o'clock in the morning, Beijing's real-time temperature is only, this temperature has hit a new low in the second half of this year, and the outdoor cold is pressing.

At 6 o'clock this morning, the real-time temperature at the observatory in the southern suburbs of Beijing was only a new low in the second half of this year.

According to the forecast, Beijing will have sunny weather during the day today, but the temperature is still relatively low. According to the forecast released by the Beijing Meteorological Observatory at 6 o'clock this morning, during the day today, Beijing will be sunny, with a north-to-south wind of 2 3 and a maximum temperature of 7; It will be cloudy at night, with a southerly to northerly wind of 1 2 and a minimum temperature of -4.

Tomorrow, Beijing will still be mainly sunny and cloudy, and the maximum temperature will rise to around 9, but the minimum temperature at night will still be only around -2.

It is expected that until December 1, the maximum temperature during the day in most areas of Beijing will be maintained between 7 11, and the minimum temperature at night will be between -4 1, and the temperature will be low in the morning and evening. y

Listen to the man who treats the light bulb as if it doesn't exist or as a wire.

Definition: 1) A short circuit is a closed circuit when the power supply is directly connected by the wire without passing through the load. The short-circuit current refers to the current when the electrical appliance is not connected, which is equivalent to the current when the positive and negative phases of the battery are connected directly by finding a wire.

(Usually this is a serious and should be avoided as much as possible in the fault of the circuit, which will cause the circuit to burn out due to excessive current and cause a fire). )

2) In a hybrid circuit, wires or switches are used to connect the two ends of a circuit component or load directly. (This is a local or partial short circuit that is required for a safety connection that does not cause burnout due to excessive current.) For example, in order to prolong its service life, when one of the filaments is broken and damaged, the special structure inside it will automatically connect the two ends of the small bulbs to make the other small bulbs work normally. )

Refers to the short circuit phenomenon of the components of the bulb in the circuit!

For example: short circuit in the bulb base, short circuit in the wiring part, short circuit in the light bulb itself, etc.!

This part is not a part, it means that there is a short circuit in this section of the light bulb in the circuit.

What does it mean when a bulb is short-circuited, open-circuited, open-circuited?

1.To put it simply, a short circuit is when the current is not directly connected to the neutral wire without passing through the filament, the live wire. Short circuits should be avoided as much as possible in daily life and work, because the current is very high and easy to cause fire.

2.Breaking the circuit means that a whole filament has been broken.

3.The open circuit is mostly used for a switch, whether the work of the node is disconnected, the open circuit and the open circuit are basically the same meaning, both of which mean that they are not passable.

Bulb short circuit is divided into short circuit of power supply, short circuit of electrical appliances, and short circuit of three-phase system. The so-called "short circuit" refers to the connection between the phase and the phase or between the phase and the ground outside the normal operation of the power system, and the basic forms of short circuit in the three-phase system are: three-phase short circuit, two-phase short circuit, single-phase grounding short circuit, two-phase grounding short circuit.

The short circuit of the power supply means that the current does not pass through any electrical appliance, and flows directly from the positive electrode to the negative electrode through the wire, and the short circuit current may cause the power supply to suffer mechanical and thermal damage or destruction, and the short circuit is usually a serious accident, and Qin Xin should try its best to prevent it.

Short circuit of electrical appliances is also called short circuit of part of the circuit, that is, a wire is connected to the vibrillation stove at both ends of the electrical appliances, and the electrical appliances are short-circuited, which is easy to burn other electrical appliances, and the short circuit is often caused by insulation damage or careless wiring.

Short circuits sometimes produce tens of thousands or even hundreds of thousands of amperes, so a lot of heat will be generated, damage the equipment, arc will melt many components in a short time, and at the same time, the generated current will also bring a certain amount of electromagnetic force.

Open circuit: It is equivalent to connecting an infinite resistor to the circuit, which will not burn the meter.

Short circuit: The current does not pass through the electrical appliance, the current is large, and it is easy to burn the meter.

A short circuit in the power supply means that in the circuit, the current does not flow through the electrical appliance, and is directly connected to the positive and negative poles of the power supply. According to Ohm's law i=u r, we know that since the resistance of the wire is small, the current on the circuit will be very large when the power supply is short-circuited.

Open circuit refers to the state that the circuit is not closed, or the wires are not connected properly, or the electrical appliances are burned out or not installed properly (such as connecting a voltmeter in series in the circuit), that is, the entire circuit is disconnected somewhere.

<> short circuit can be explained by parallel connection, that is, a wire without resistance and a resistor with a resistance value are connected in parallel, we say that this resistance is shorted;

The open circuit can be explained in series, a wire without resistance and a resistor with a resistance value are connected in series, we disconnect the wire, it is said that the circuit is broken.

1. Short circuit and open circuit problem.

A short circuit is a closed circuit in which the current does not pass through the electrical appliance. Short circuits include local short circuits and power supply short circuits. The power supply is short-circuited, the current is very strong, and it will burn out the power supply.

In the home circuit, the electrical appliances are connected in parallel, and in the event of a short circuit, if there is no safety device, the wire will heat up sharply, which will lead to a disaster.

A circuit that is broken somewhere is called an open circuit.

2. How to judge the short circuit and open circuit in the circuit.

When two lights are connected in series, if only one light is not on, the light that is not on must be short-circuited (local short-circuit);

If neither light is on, the circuit must be open.

If only one light is not lit, it must be that the branch of the lamp that is not lit must be broken;

If neither light is on, it may be a broken trunk road. In a parallel circuit, the fault cannot be a short circuit, and if it is short, the power supply will burn out.

Short circuit refers to the phenomenon that in the electrical circuit, due to the damage of the insulation layer of the bare wire or insulated wire, the phase wire and the phase wire, the phase wire and the neutral line or the ground collide with each other in the case of very little resistance or no passing load, resulting in a sudden large increase in current.

Causes: 1. The current does not pass through the electrical appliances and is directly connected to the two poles of the power supply;

2. The wires are directly connected to both ends of the electrical appliances, resulting in a short circuit in some circuits;

3. Damage to components, aging of insulating materials of wire equipment, etc.

Because the resistance r of the wire is very small, according to Ohm's law i=u r, the current on the circuit will be very large when there is a short circuit.

Excessive current can damage the battery or power supply, or even cause a fire due to the high temperature of the wire.

The bulb has its own resistance and there is an electric current flowing through it during normal operation. A short circuit is caused by the formation of a path at both ends of the resistance (equivalent to the parallel connection between the bulb and the wire) due to some reasons (wire deformation, water ingress, etc.), resulting in the current not passing through the bulb resistor, and the voltage at both ends of the bulb is 0.

There are two reasons for a short circuit in a bulb:

The first is a short circuit in the power supply: it means that the current does not flow through the electrical appliances and is directly connected to the two poles of the power supply; (will burn out the circuit).

The second is the short circuit of the electrical appliance Short circuit: It refers to the direct passage of the current without passing through the electrical appliance; (It is common to use wires to connect directly to both ends of the appliance).

In both cases, the bulb will short-circuit and not light up.

The positive and negative wires are produced by contact with each other.

The bulb has a certain resistance and also has a rated voltage and a rated current.

A short circuit in a bulb is when the current passing through the bulb exceeds the rated current or the voltage at both ends of the bulb exceeds the rated voltage of the bulb.

Cause: When the circuit resistance of the bulb is very small, that is, there is no other electrical appliance or resistance other than the bulb to divide the voltage, and the voltage at both ends of the bulb exceeds the rated voltage of the bulb or the current through the bulb exceeds the rated current of the bulb, the bulb will be short-circuited.

Solution: Connect the bulb in series with a suitable resistor or replace it with a suitable power supply.

Open circuit and open circuit are the same meaning, that is, a line is disconnected from the middle, and a short circuit is the current connection between the positive and negative lines, which is very dangerous

A short circuit in a bulb is a short circuit in a circuit, where the live wire and the neutral wire are directly connected. 220V live wire zero filament can not get the voltage will definitely not be lit, open circuit and open circuit means that the circuit is connected at the end of a certain point, and the circuit is connected and disconnected, and the circuit is formed at the end of the circuit. The filament is equivalent to a thread, so it does not emit light.

Open circuit: also known as open circuit, refers to the fact that the resistance is too large due to disconnection in a certain part of the circuit, and the current cannot pass through normally, resulting in zero current in the circuit.

The voltage at both ends of the break point is the power supply voltage, which generally does not damage the circuit. For example, it is possible that the wire is broken, or the electrical appliance (such as the filament in the light bulb) is disconnected from the circuit, etc.

Short circuit: refers to the light bulb or the metal of the zero live wire of the line directly put together, resulting in a short circuit. At this time, the resistance on the line is the smallest and the current is the largest, which is easy to cause electrical fire.

A short circuit in a bulb is a phenomenon in which the two poles of the bulb are connected together, or the two wires of the bulb are connected together.

This phenomenon is more serious, and the automatic clutch will jump off.

That's what we usually mean by UMC.

A short circuit is that the filament of the bulb is broken and cannot form a circuit, and the bulb will not light up and open the circuit is equivalent to turning on the switch, which is also unable to form a circuit.

None of the above bulbs will light up.