PESEX TERMS AND CONCEPTS

• Although dipoles are electrically neutral, their charges are arranged such that one end is more positive than the other.
• A capacitor is an electrical device used to store electric energy. It is basically two metal plates placed parallel to each other, really close without touching.
• A parallel-plate capacitor is a system composed of two identical parallel-conducting plates separated by a distance.
• Capacitors with different physical characteristics (such as the shape and size of their plates) store different amounts of charge for the same applied voltage across their plates.
• Capacitance is the ability of a material or circuit to collect and store energy in the form of an electrical charge.
• capacitance the unit coulomb per volt, known as farad (F), named after Michael Faraday.
• Each plate of a capacitor is given an equal but opposite charge, with one plate having a charge +Q and the other charge –Q. The opposite charges attract one another and move to the inner surface of the capacitor.
• The electric field between two plates is uniform going from the positive to the negative plate. The potential of the positive plate is positive and the potential of the negative plate is negative.
• In a circuit, a capacitor obtains its charge when a potential difference is applied across its terminals.
• When devices are connected in parallel, they share a common point (junction) at which the potential is the same for all conductors.
• An electric circuit is a closed conducting path that allows charges to flow from one point to another continuously.
• a circuit contains a power supply, a device that dissipates energy, the resistor (used to reduce current flow) and wires that connect all the parts together.
• Current is the steady flow of charge.
• I=Q/t This equation gives us the unit coulomb per time, known as ampere (A), named after French physicist André Marie Ampére
• current is defined as the flow of positive charges.
• The conventional current direction is the direction of flow of positive charges.
• Current flows from the positive terminal to the negative terminal; From higher potential to lower potential
• Electrons actually move away from the negative end of the wire toward the positive end, opposite of the conventional flow
• An electric field is applied to the ends of a conductor by the battery (or power supply) causing positive charges to move in the direction of the field and the negative charges move against the direction of the field.
• It can be also explained that a potential difference is applied between two ends of the conductor causing positive charges to move from higher potential to lower potential (from positive to negative terminal) and the negative charges move from lower potential to higher potential (from negative to positive terminal).
• when a positive charge carriers reach the low potential end of the conductor, they do not stop there and accumulate. Instead, they keep going to the battery, which is the conductor itself.