The battery hypothesis
Suppose we have a 9 volts standard battery. Let's set up 2 situations.
1/ Disconnected (being in air, or near infinity resistance conductor).
2/ Short circuit (conductor with almost zero resistance).
In general thinking, a person would say in situation 1 the battery does not give out power and the battery life would remain indefinitely. In situation 2, the battery is drawing its max power and the battery life will drain up shortly.
This notion of thinking is correct in observation, but not correct in logic. First, air is a bad conductor just as metal is a bad insulator. Let's take it to finite science and give a resistance value to both air and metal. Following omh's law V=IR, we can see that in air, voltage will be high and the infitestimal current exist. The power from the battery will be P=IV, where V is the differential voltage across the air (not battery). In metal, the voltage is low and the current is high. The power from the battery will be P=IV, where V is the differential voltage across the metal. In both cases, the power draw is the same!
In conclusion, the battery continuously give out the same amount of power whether connected or disconected.
The final question would be why the battery die? It is dead not because it has certain amount of energy but rather because of the heat generate by high amperes that destroy the chemical structure within. To put this into real application, one could use high voltage low current or provide a heat sink to remain cool.
Suppose we have a 9 volts standard battery. Let's set up 2 situations.
1/ Disconnected (being in air, or near infinity resistance conductor).
2/ Short circuit (conductor with almost zero resistance).
In general thinking, a person would say in situation 1 the battery does not give out power and the battery life would remain indefinitely. In situation 2, the battery is drawing its max power and the battery life will drain up shortly.
This notion of thinking is correct in observation, but not correct in logic. First, air is a bad conductor just as metal is a bad insulator. Let's take it to finite science and give a resistance value to both air and metal. Following omh's law V=IR, we can see that in air, voltage will be high and the infitestimal current exist. The power from the battery will be P=IV, where V is the differential voltage across the air (not battery). In metal, the voltage is low and the current is high. The power from the battery will be P=IV, where V is the differential voltage across the metal. In both cases, the power draw is the same!
In conclusion, the battery continuously give out the same amount of power whether connected or disconected.
The final question would be why the battery die? It is dead not because it has certain amount of energy but rather because of the heat generate by high amperes that destroy the chemical structure within. To put this into real application, one could use high voltage low current or provide a heat sink to remain cool.
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