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Answer: Let’s start with what you mean by the wire being “not connected to anything.” You probably mean that the wire isn’t connected as part of a circuit. But, a wire must be part of a circuit for there to be a flow of electric current moving through it. For instance, let’s say the wire is wrapped into a coil around a non-conducting medium such as wood, but neither end of the wire is connected, and a magnet is rotated around the coil. The motion of the magnet in relation to the coil will generate a magnetic field in the coil, but no current results. It’s not that the current disappears, it’s that the current wasn’t there in the first place.

Answer: Electricity is important in many ways. It provides us with light for our homes and schools, and as well, runs our devices, such as phones, computers, TVs, and home appliances.

Answer: Induction is the process by which an object or material becomes magnetized by an external magnetic field. But, when the magnet stops working within an object or a specific type of material, then it is “saturated.” In the saturated state, a magnet cannot be made any stronger by induction.

Answer: There are two different forms of inductance: magnetic and electric, and they are related to two different aspects of the electromagnetic force. Magnetic inductance is the creation of a magnetic field in a substance by another magnetic field. The magnetic permeability of that substance is measured by how magnetized it becomes to an applied magnetic field. Electrical inductance is the creation of an electric current in a circuit by an external magnetic field that is moving relative to it. The electrical equivalent of magnetic permeability is permittivity, which measures how much resistance a substance has to the induction of an electric charge. The relationship between permeability and electrical inductance is complicated, but broadly, the more easily a magnetic field can be induced in a substance, the more readily an electric charge can be induced in it.

Answer: Electricity is always trying to get to the ground. If something that conducts electricity gives it an easy path to the ground, then electricity will take that path! Kites and kite strings can conduct electricity, and so can the human body. If your kite gets caught in a power line, you and the kite will provide electricity with a direct path to the ground. Electricity will travel through the kite, down the kite string, into your hands and arms, and down through your body and feet.

That’s why you must always fly kites in open areas, keeping them away from overhead power lines and electrical equipment. If your kite or anyone else’s kite touches the power lines, do not attempt to retrieve it or any other foreign object tangled in wires. Stay away and call 911 and SCE at 800-611-1911 to report the hazard.

Answer: Both of these items could make a magnet stronger. If you cover a magnet with iron, it becomes permeable to magnetic fields. If the magnet is really strong, the iron would eventually become a magnet itself. However, if the original magnet is too weak, the iron would not become magnetized. If an iron core is placed inside a magnet, it would increase the strength of the field, because the core will become magnetized as well.

Answer: The Expert is not familiar with "neodynamic" magnets. Perhaps you are thinking of neodymium magnets? These magnets, which are the most powerful permanent magnets ever developed, can indeed conduct electricity. (Permanent magnets, like toy horse-shoe magnets or refrigerator magnets, don't need an electrical current running through them to make them magnetic.) In fact, because electricity and magnetism are two sides of the same force, any permanent magnet is an electrical conductor.

Answer: A substation lowers electricity’s voltage. From the power plant where it is generated, high voltage electricity travels along big transmission wires supported by tall towers into neighborhoods. The substations in neighborhoods contain equipment that reduces the voltage so that it can then travel on smaller power lines that branch out down streets, either on overhead power lines or lines buried underground.

Answer: When you plug in and turn on a device, you “close” the electrical circuit flowing from where the electricity enters the house at the circuit box, through wires inside the walls, and into the device. When you turn off the device, the circuit is “opened” and this breaks the flow of electricity.

Answer: Yes. A magnet can induce an electric current in a circuit made of any conducting material, and superconductors are no exception. In fact, because superconductors offer zero resistance to the flow of electrons, a superconducting circuit always has a small current flowing through it.

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