Measuring the voltage accumulating on a capacitor.
Connect the circuit (a pushbutton, a resistor and a capacitor).
Connect the probe of the meter to the capacitor,
See the voltage rise (and drop when you shut down the power.)
Sounded pretty simple but a few problems arose.
First of all I couldn't get any voltage on the emter to begin with.
So I changed the capacitor and it seemed to work.
Secondly, I eventually read in the book that the voltage in the capacitor should eventually reach the same voltage as the source.
My dc adaptor was set to 12V but i was reading about 17.5 Volts from my capacitor.
What the hell was going on?
After a small head ache, i realize that simply, my dc adaptor is faulty and give me voltage much higher than what it suppose to.
I guess i'll try to send it back to the electronics store.
Thats it for this experience, after the experience, re-reading the chapter on capacitor in both the Make: electronics book, and the "for dummies" book, plus watching the make youtube video, i have a better understanding of capacitors but still have a question about experiment number 8 that i cannot find the answer for.
(why the doesn't the circuit just ignore the capacitor, since there is no resistance in the relay so it is just like a direct wire. So you should have a result exactly similar to the same circuit without a capacitor.
Also since the circuit clearly doesn't ignore the capacitor, and presumably, the relay coil only use the power from the capacitor and nothing from the power supply, why does the capacitor get all of the voltage?)
if anyone can explain this to me, i would be very grateful!
Thank you!
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