This is not strictly a homework question, but I consider it to be pretty basic and thus probably best answered in this forum.
I am working my way through Make: Electronics.
Experiment 9: Time and Capacitors asks you to construct the following circuit:
The purpose is to demonstrate that a capacitor can allow a signal to pass through it. By pressing switch A, the capacitor charges and briefly illuminates the LED. Once "fully" charged, the LED no longer illuminates regardless of pressing switch A. To reset the capacitor, pressing switch B discharges the capacitor and allows you to illuminate the LED again with switch A.
Now, my question is why is the 10k ohm resistor necessary? Shouldn't a simple short circuit discharge the capacitor?
I templated this in circuits.io and it doesn't work, which is expected. But why? If the resistor is necessary to safely discharge the capacitor, why must it be connected to the negative bus? Why does it not work to put the resistor in the short circuit with switch B?
The following circuit illustrates what I'm imagining. After the capacitor has been charged, why doesn't pressing switch B create the short circuit path in yellow to discharge the capacitor?
If I had to guess, I suspect my confusion lies in a misunderstanding of the way capacitors work.
Thanks.
I am working my way through Make: Electronics.
Experiment 9: Time and Capacitors asks you to construct the following circuit:
The purpose is to demonstrate that a capacitor can allow a signal to pass through it. By pressing switch A, the capacitor charges and briefly illuminates the LED. Once "fully" charged, the LED no longer illuminates regardless of pressing switch A. To reset the capacitor, pressing switch B discharges the capacitor and allows you to illuminate the LED again with switch A.
Now, my question is why is the 10k ohm resistor necessary? Shouldn't a simple short circuit discharge the capacitor?
I templated this in circuits.io and it doesn't work, which is expected. But why? If the resistor is necessary to safely discharge the capacitor, why must it be connected to the negative bus? Why does it not work to put the resistor in the short circuit with switch B?
The following circuit illustrates what I'm imagining. After the capacitor has been charged, why doesn't pressing switch B create the short circuit path in yellow to discharge the capacitor?
If I had to guess, I suspect my confusion lies in a misunderstanding of the way capacitors work.
Thanks.