Electricity Review Questions
How are charges transferred through conduction? By Direct Contact
How are charges transferred through induction? Charges in an uncharged metal object are rearranged without direct contact with a charged object.
How are charges transferred through friction? Electrons are “wiped” from one object onto another.
What is voltage? Voltage is a measure of how much work is needed to move a charge between two points.
What is current? The amount of electricity flowing through a circuit.
What is resistance? Resistance is the opposition presented to the current by a material or device. Will allow charges to flow, but they do not flow freely.
What is the relationship between current and resistance? Resistance increases, Current decreases Resistance decreases, Current increases
What is the relationship between voltage and current? Voltage increases, Current increases Voltage decreases, Current decreases
What are the three parts of an electric circuit? Wire, Load, Energy Source
What is electric discharge? The release of electricity stored in a source.
What is static electricity? Electric charge at rest. Examples: charged balloon, clothes stuck together from dryer
What is a conductor? A material in which charges can move freely.
What is an insulator? A material in which charges cannot move.
Examples of conductors and insulators: Conductors: Iron, copper and other metals, water Insulators: Glass, Wood, Plastic, Cotton
What is a resistor? An object that supplies resistance in an electrical circuit.
What is an electric field? The space around a charged object in which another charged object experiences an electric force.
What is a fuse? A thin strip of metal that melts when too much current is flowing through it, creating an incomplete circuit.
What is a circuit breaker? A switch that automatically opens if the current is too high.
How can you increase the magnetic field in an electromagnet or solenoid? Add more coils of wire or increase current.
What is a series circuit? A circuit in which the parts are joined one after another so that the electricity has only one pathway.
What is a parallel circuit? A circuit in which the parts are joined in branches, giving electricity more than one pathway.
What are some advantages of a parallel circuit? If one load is missing or broken, charges will still flow through the other branches. You can use one light or appliance at a time.
What types of circuits are used most often in homes? Parallel
What does a wire carrying electric current produce? A magnetic field
What is a solenoid? A coil of wire with an electric current in it.
What is an electromagnet? A coil of wire that has an iron core and acts as a magnet when an electric current is in the coil.
How do you make magnets using electricity? Make a coil of wire and send a current through it.
How do you make electricity using a magnet? Move a magnet in and out of a coil of wire, or spin a coil of wire inside a magnet.
What are some ways electromagnetism is used in our daily lives? Electric Motors, Cars, Generators, Doorbells, Computers, Computer disks, Headphones, Cell Phones, Satellites, Television, Audio Recoding Devices, Speakers, Video Cassettes, Microphones
What are four electrical safety tips? Make sure the insulation on cords is not worn. Do not overload circuits by plugging in too many electrical devices. Do not use electrical devices while your hands are wet or while you are standing in water. Never put objects other than a plug into an electrical outlet.