A 20-mF capacitor charged to 2.0 kV and a 40-mF capacitor charged to 3.0 kV are connected to each other, with the positive plate of each connected to the negative plate of the other. What is the final charge on the 20-mF capacitor after the two are so connected? Select one: a. 80 mC b. 40 mC с. 39 mc d. 27 mC е. 52 m

You need to construct a 100 pF capacitor for a science project. You plan to cut two L x L metal squares and insert small spacers between their corners. The thinnest spacers you have are 0.20 mm thick. What is the proper value of L?

What speed must the proton have in the velocity selector diagrammed below to make it through the capacitor plates undeflected?     a. 1.24 x 105 m/s   b. 1.83 x 105 m/s   c. 7.53 x 104 m/s   d. 2.22 x 106 m/s   e. 2.50 x 104 m/s

A fully charged capacitor can store 500 J of energy. Assuming it is charged using the typical 120V of potential, what must be the capacitance? a. 23 mF b. 69 mF c. 128 mF d. 424 mF