How to judge whether the circuit is short circuit or open circuit from the presence of voltmeter and current indication Students said that in the series circuit, the small light bulb is not on. When the ammeter in series with the small light has a number, the small light is not normal. If the ammeter has no number, it means that the small light is OK. Is he right? Explain it. Thank you

How to judge whether the circuit is short circuit or open circuit from the presence of voltmeter and current indication Students said that in the series circuit, the small light bulb is not on. When the ammeter in series with the small light has a number, the small light is not normal. If the ammeter has no number, it means that the small light is OK. Is he right? Explain it. Thank you

Not all right. In series circuit, the current is equal everywhere. The ammeter shows that there is electricity, the circuit is a path, and the bulb is not on. The ammeter does not show that there is no electricity, the circuit is open, and it is impossible to judge whether there is a problem with the small bulb

There's a short circuit in the circuit. There's a lot of voltage and current

There is current but no voltage. The current will increase sharply, and the voltage at the short circuit point is zero

Why is the open circuit current 0 and the short circuit voltage 0?

Ohm's law v = IR, the current I is inversely proportional to the resistance R, the larger R, the smaller I, the open circuit is like an infinite resistance, so I = 0
The voltage is proportional to the resistance R. the larger the resistance, the greater the voltage at both ends. The short circuit is like a 0 ohm resistance, so the voltage at both ends is like 0

Which is the ideal voltage source and ideal current source in series to supply power to the load

1. When the load is less than a critical value, the voltage source provides energy and the current source absorbs energy. 2. When the load is equal to a critical value, the voltage source provides energy and the current source neither provides energy nor absorbs energy, which means that there is no energy. 2. When the load is greater than a critical value, both the voltage source and the current source provide energy