A capacitor is a simple electrical device. It consists of three parts sandwiched tightly together. Two outer layers made of conductors are separated by an insulating middle layer. A simple circuit is made with a capacitor, a wire, and a battery. When fully connected, which of the following occurs? Both plates become positively charged. The net charge on the capacitor increases zero. The insulator stops the flow of electricity. The conductor stops the flow of electricity.

A capacitor is a device that is used to store up electrical potential energy. It consists of three parts sandwiched tightly together. Charges from one of the outer pieces are pumped around the circuit onto the other outer layer. In order for the capacitor to be able to build up as much potential as possible, what type of material should the outer layers be made of? A conductor An insulator A radiator A semiconductor

Q.30. Read the following paragraph and answer the questions that follow. A capacitor is a system of two conductors separated by an insulator. The two conductors have equal and opposite charges with a potential difference between them. The capacitance of a capacitor depends on the geometrical configuration (shape, size and separation) of the system and also on the nature of the insulator separating the two conductors. They are used to store charges. Like resistors capacitors can be arranged in series or parallel or a combination of both to obtain desired value of capacitance. (i) Find the equivalent capacitance between points A and B in the given diagram. (ii) A dielectric slab is inserted between the plates of a parallel plate capacitor. The electric field between the plates decreases. Explain. (iii) A capacitor A of capacitance C having charge Q is connected across another uncharged capacitor B of capacitance 2C. Find an expression for (a) the potential difference across the combination and (b) the charge lost by capacitor A. Or (iii) Two slabs of dielectric constants 2K and K fill the space between the plates of a parallel plate capacitor of plate area A and plate separation as shown in figure. Find an expression for capacitance of the system. Q.31 An interesting characteristic of the series LCR circuit is the phenomenon of resonance. The phenomenon of resonance is common among systems that have a tendency to oscillate at a particular frequency. This frequency is called the system's natural frequency. If such a system is driven by an energy source of a frequency that is near the natural frequency, the amplitude of the oscillation is found to be large. Resonant circuits have a variety of applications, for example, in the tuning mechanism of a radio or a TV set. The antenna of a radio accepts signal from many broadcasting stations. The signals picked up in the antenna acts as a source in the tuning circuit of the radio, so the circuit can be driven at many frequencies. But to hear one particular radio station, we tune the radio, so that resonant frequency of the circuit becomes nearly equal to the frequency of radio signal received.  Now, answer the following questions:- (1) If the value of 'C' is decreased in a series LCR circuit, then resonant frequency (a) increases. (b) decreases. (c) is not affected. (d) is reduced to zero. (ii) Power factor is one for (a) pure inductor (b) pure capacitor (c) pure resistor (d) either an inductor or a capacitor (iii) As X_{L} = X_{C} in a series LCR circuit, the impedance (a) purely resistive (b) purely inductive (c) purely capacitive (d) capacitive or inductive (iv) Power factor of an inductive series LCR circuit can be improved by using (a) a capacitor in series. (b) a capacitor in parallel with the capacitor of LCR circuit. (c) a capacitor in parallel with the series LCR circuit. (d) an inductor in series with the series LCR circuit. Or (iv) Current in the circuit is wattless if (a) inductance in the circ

A complete circuit with a capacitor is turned on. Charges are moved from one plate of the capacitor, through the battery, and all the way around to the other plate. Which of the following occur during that time? Kinetic energy is decreased. Thermal energy is decreased. Chemical potential energy is increased. Electrical potential energy is increased.

A parallel plate capacitor is charged by a battery after charging the capacitor, the battery is disconnected and if a dielectric plate is inserted between the plates, then which one of the following statements is not correctincrease in the stored energydecrease in the potential differencedecrease in the electric fieldincrease in the capacitance

A parallel plate capacitor is charged so that a total charge of +Q ends up on the positive plate, and -Q on the negative plate.The capacitor is then disconnected from rest of the circuit. Next, I push the two plates slightly closer together. Which statement is true about the electric field and the voltage difference between the plates?