Capacitors and Capacitance (0428)

Capacitors and Capacitance

We did a quiz about the Kirchhoff's law.

We use Kirchhoff's Current Law and Kirchhoff Voltage Laws to find 3 equations to find the voltage, current and power of each line, and find the total power of them.

We begin to learn Capacitance. it can store charges, the unit is F, the symbol is C.In this photo, Q is charges and V is voltage, and we know the equation Q=VC, and we can find the work done by capacitance is W= 1/2*V^2*C

We plotted our data point using excel. The graph turned out to be 1/x curve.

K here is the dielectric constant. The formula Q=K*epsilon_not *E*A derived from E=Q/epsilon_not*A (Gaussian's surface chapter). The K constant represents different materials will behave differently in magnitude.

Here is some assigned problem. We were asked to find the side of the rectangular plate. Information needed was given.

We were given two capacitors. We measured capacitance of each capacitors individually. Then we obtained the results of capacitors in series and parallel circuit. Interestingly, to find the equivalent capacitors, we would have to do the opposite process to find the equivalent resistance

Our work to find equivalent capacitor. First,we noticed that top two capacitors were in series, so we combined them. Then we combined the two bottom ones. Now, we had a total of 3 parallel capacitors. we just needed to add them up.

The 3 circuits are parallel to each other. We first find the combined the two capacitors of the top ones, which were in series. Then we combined that capacitor to the bottom one, which were parallel. We redrew our circuit which just a single battery and a single equivalent capacitor. We then find the Q1= C1*V1. Q1=Q2. Therefore, C1V1= C2*V2. We now have V2 and V1. V3= V1+V2.=Vb