Discharging capacitor half life

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Discharging capacitor half-life refers to the time required for a capacitor's voltage to decrease to half of its initial value. This process occurs exponentially, represented mathematically by the equation v = V_0 e^(-t/RC), which can also be expressed in a different base. The half-life can be calculated as RC/log_e(2), indicating that this time period consistently reduces the voltage by half. The concept of half-life is applicable in various decay and growth processes, highlighting its significance beyond just capacitors. Understanding this principle is crucial for analyzing exponential decay in different contexts.
Googl
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What is meant by discharging capacitor half life (the description). I seem to be getting different description, I would just like for someone to confirm it here for me please.
 
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If discharged through a resistor the capacitor voltage reduces exponentially via the equation

v = V_0 \, e^{-\frac{t}{RC}}

Mathematically it's easy to represent an exponential of one base in other other base.

In this case the above exponential can be re-written as

v = V_0\, 2^{-\frac{t}{\log(2) \, RC}}

where "log" is the natural logarithm.

From the above equation you can see that the "half life" is RC/\log_e(2)
 
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Thanks Uart,

I understand that, how would you describe half life (not mathematically or through equations).

uart said:
If discharged through a resistor the capacitor voltage reduces exponentially via the equation

v = V_0 \, e^{-\frac{t}{RC}}

Mathematically it's easy to represent an exponential of one base in other other base.

In this case the above exponential can be re-written as

v = V_0\, 2^{-\frac{t}{\log(2) \, RC}}

where "log" is the natural logarithm.

From the above equation you can see that the "half life" is RC/\log_e(2)
 
Googl said:
Thanks Uart,

I understand that, how would you describe half life (not mathematically or through equations).

Well obviously, it's the time that you have to wait until the voltage is half of it's original value. That's how I'd describe it.
 
Half life of a quantity is the time it needs so that the quantity is reduced to half of its original value.

In the example of Uart, half life of the voltage is the time it gets for the voltage to reduce to the half of its starting value , that is the time it needs to go from V_0 to \frac{V_0}{2}
 
Thanks.
 
It may be worthwhile pointing out that this 'half life' applies wherever you start. So, every period of one half life decreases the voltage by a factor of two. This 'exponential' function is the only one with this property afaik. It applies in many examples of decay and growth processes (even bloody compound interest!).
 
uart said:
you can see that the "half life" is RC/\log_e(2)


Just correcting a typo above. That should of course have been RC \, \log_e(2)
 
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