Sensing electrically Flashcards
Electric Charge
Definition: Electric charge is a fundamental property of matter that causes it to experience a force when placed in an electric and magnetic field. It can be positive or negative.
Example: Protons carry a positive charge, while electrons carry a negative charge.
How to Identify: Look for objects or particles that exhibit attraction or repulsion due to the presence of electric fields.
Electric Current
Definition: Electric current is the flow of electric charge (usually electrons) through a conductor, typically measured in amperes (A).
Example: The current in a wire increases when a battery is connected to it.
How to Identify: Electric current is present in any circuit where electrons move from one point to another, typically in a closed loop.
Conduction and Insulation
Definition: Conduction refers to the transfer of electric charge through a material, while insulation refers to materials that prevent the flow of electric charge.
Example: Metals like copper are conductors, while rubber and plastic are insulators.
How to Identify: Conductors allow electricity to flow through them, whereas insulators resist the flow of electricity.
Generators
Definition: A generator is a device that converts mechanical energy into electrical energy by moving a conductor through a magnetic field.
Example: Hydroelectric dams use water flow to turn turbines that generate electricity.
How to Identify: Generators have moving parts (turbines or coils) and produce electrical power when mechanical energy is applied.
AC and DC
Definition: AC (Alternating Current) is the flow of electric charge that reverses direction periodically, while DC (Direct Current) flows in only one direction.
Example: AC is used in household power supplies, while DC is used in batteries.
How to Identify: AC power fluctuates in direction, while DC flows in a consistent direction.
Circuit Diagrams - Series and Parallel Circuits
Definition: Circuit diagrams represent the layout of electrical components in a circuit. In a series circuit, components are connected end-to-end, while in a parallel circuit, components are connected across common points.
Example: In a series circuit, if one bulb blows, all bulbs go out; in a parallel circuit, other bulbs remain on.
How to Identify: Series circuits have components connected in a single line, while parallel circuits have components connected in separate branches.
Potential Difference
Definition: Potential difference (voltage) is the difference in electric potential between two points in a circuit, which drives the flow of electric current.
Example: A 9V battery provides a potential difference of 9 volts between its terminals.
How to Identify: Potential difference is measured across components, and it determines the amount of energy transferred by electrons.
Electrolysis
Definition: Electrolysis is a process where electrical energy is used to drive a non-spontaneous chemical reaction, typically involving the decomposition of water or other compounds.
Example: Electrolysis of water produces hydrogen and oxygen gases.
How to Identify: Electrolysis involves the use of two electrodes in an electrolyte solution with an applied current.
Redox Reactions
Definition: Redox reactions involve the transfer of electrons between two substances, with one being oxidized (losing electrons) and the other reduced (gaining electrons).
Example: In the reaction between hydrogen and oxygen to form water, hydrogen is oxidized, and oxygen is reduced.
How to Identify: Look for reactions where one substance gains electrons (reduction) and the other loses electrons (oxidation).
Reactivity Series
Definition: The reactivity series is a ranking of metals based on their reactivity, with the most reactive metals at the top and the least reactive at the bottom.
Example: Potassium is more reactive than gold, which is less reactive than platinum.
How to Identify: The position of metals in the series indicates how readily they react with other substances, like acids or water.
Electroplating
Definition: Electroplating is the process of using electric current to deposit a layer of metal onto a surface, typically to prevent corrosion or improve appearance.
Example: Silver-plated jewelry uses electroplating to coat a base metal with a thin layer of silver.
How to Identify: Electroplating involves passing current through a solution containing metal ions to deposit the metal on an object.
Bioelectrogenesis
Definition: Bioelectrogenesis is the production of electrical energy by living organisms, such as bacteria or certain fish species.
Example: Electric eels generate electric fields to stun prey.
How to Identify: Look for organisms that can generate electrical impulses or currents for communication, defense, or hunting.
Resistivity
Definition: Resistivity is a property of a material that quantifies how strongly it resists the flow of electric current. It is inversely related to conductivity.
Example: Materials like copper have low resistivity, while rubber has high resistivity.
How to Identify: Resistivity is characteristic of materials and is influenced by temperature and composition.
Ohmโs Law
Definition: Ohmโs Law states that the current passing through a conductor is directly proportional to the potential difference (voltage) across it and inversely proportional to its resistance.
Example: If the voltage is increased, the current increases, provided the resistance remains constant.
How to Identify: The relationship between voltage, current, and resistance in a circuit is described by the formula
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Electrical Circuitry of the Human Body
Definition: The human body can conduct electrical impulses, particularly in the nervous system and heart, where electrical signals regulate bodily functions.
Example: Electrical impulses are essential for the transmission of nerve signals and the contraction of muscles.
How to Identify: Electrical signals in the body are responsible for communication between neurons and organ systems, such as the heartโs rhythm.
Cardiac Conduction System
Definition: The cardiac conduction system is a network of specialized cells that carry electrical impulses to coordinate the contraction of the heart muscles.
Example: The sinoatrial (SA) node in the heart initiates electrical impulses that cause the heart to beat.
How to Identify: Look for the pathway that electrical signals take through the heart, from the SA node to the atrioventricular (AV) node, bundle of His, and Purkinje fibers.
Sensors
Definition: Sensors are devices that detect physical properties (like light, temperature, or pressure) and convert them into electrical signals that can be measured.
Example: A temperature sensor in a thermostat measures the temperature and adjusts the heating system accordingly.
How to Identify: Sensors detect changes in their environment and produce a corresponding electrical signal to indicate these changes.
