We connect capacity and a bubble in series . It is actually charging the capacitor, and the use of the bubble is for safety purpose. Also we gonna use it to see if the capacitor is charged completely.
We are calculating the final potential difference after the capacitor is fully charged. However, the actual value and our calculated value has a huge difference.
We use logo pro to collect data such as voltage and current when charging and discharging the capacitor. We plot the graph as a function of time, observing that the final voltage goes to a constant as time increase. When charging, the final voltage is close to the battery voltage, and final voltage is 0 when discharging.
The time constant. We derive a new formula to determine the change of voltage and current and charge about the capacitor when we charge or discharge it in a circuit. The time constant is defined as RC.
We give a very high voltage to a capacitor, and it exploded. This experiment tells us the danger that voltage supplied to capacitor is much higher than its normal voltage range.
We graph the current change based on the formula we got. Idealy , after fully charged, the voltage capacitor can supply is equal to the battery volage .
When charging the capacitor, we should treat it as an open switch. However, after charge it, this type of question become the one we did from the previous lab. We need to determine the current direction. We need to treat it as a battery, and based on each loop the net voltage is 0 to set equation.
Summarize: The relationship between voltage or current and time has an exponential function relationship, and it is a matter of resistance connected in circuit and the capacitor. Here we have a time constant in the function. When we did circuit question that contains capacitor, we should treat it as an open switch when it starts to charge it, and a battery after we are gonna use it.
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