2. Charge q is fired through a small hole in the positive plate of a capacitor. a. If q is a positive charge, does it speed up or slow down inside the capacitor? Answer this question twice: i. Using the concept of force. ii. Using the concept of energy. b. Repeat part a for q as a negative charge.

a parallel-plate capacitor with area 0.200 m2 and plate separation of 3.00 mm is connected to a 6.00-V battery. (a) What is the capacitance? (b) How much charge is stored on the plates? (c) What is the electric field between the plates? (d) Find the magnitude of the charge density on each plate. (e) Without disconnecting the battery, the plates are moved farther apart. Qualitatively, what happens to each of the previous answers?

(a) A certain parallel-plate capacitor has plates of area 4.00 m2 , separated by 0.0100 mm of nylon, and stores 0.170 C of charge. What is the applied voltage? (b) What is unreasonable about this result? (c) Which assumptions are responsible or inconsistent?

The electric field strength between two parallel conducting plates separated by 4.00 cm is 7.50 104 V/m. (a) What is the potential difference between the plates? (b) The plate with the lowest potential is taken to be at zero volts. What is the potential 1.00 cm from that plate (and 3.00 cm from the other)?

In nuclear fission. a nucleus splits roughly in half. (a) What is the potential 2.00 10-14 m from a fragment that has 46 protons in it? (b) What is the potential energy in MeV of a similarly charged fragment at this distance?

To form a helium atom, an alpha particle that contains two protons and two neutrons is fixed at one location, and two electrons are brought in from far away, one at a time. The first electron is placed at 0.6001010 m from the alpha particle and held there while the second electron is brought to 0.6001010 m from the alpha particle on the other side from the first electron. See die final configuration below, (a) How much work is done in each step? (b) What is the electrostatic energy of die alpha particle and two electrons in the final configuration?

(a) What is the capacitance of a parallel-plate capacitor with plates of area 1.50 m that are separated by 0.0200 mm of neoprene rubber? (b) What charge does it hold when 9.00 V is applied to it?

A simple and common technique for accelerating electrons is shown in Figure 7.46, where there is a uniform electric field between two plates. Electrons are released, usually from a hot filament, near the negative plate, and there is a small hole in the positive plate that allows the electrons to continue moving, (a) Calculate the acceleration of the electron if the field strength is 2.50104 N/C . (b) Explain why the electron will not be pulled back to the positive plate once it moves through the hole. Figure 7.46 Parallel conducting plates with opposite charges on them create a relatively uniform electric field used to accelerate electrons to the right. Those that go through the hole can be used to make a TV or computer screen glow or to produce X- rays.

A lightning bolt strikes a tree, moving 20.0 C of charge through a potential difference of 1.00102 MV. (a) What energy was dissipated? (b) What mass of water could be raised from 15 °C to the boiling point and then boiled by this energy? (c) Discuss the damage that could be caused to the tree by die expansion of the boiling steam.

Four parallel metal plates P1, P2, P3, and P4, each of area 7.50 cm2, are separated successively by a distance d = 1.19 mm as shown in Figure P25.34. Plate P1 is connected to the negative terminal of a battery, and P2 is connected to the positive terminal. The battery maintains a potential difference of 12.0 V. (a) If P3 is connected to the negative terminal, what is the capacitance of the three-plate system P1P2P3? (b) What is the charge on P2? (c) If P4 is now connected to the positive terminal, what is the capacitance of the four-plate system P1P2P3P4? (d) What is the charge on P4?