Explanation: The best material to use for the core of a electromagnet is iron. Iron, nickel, cobalt and some of the rare earths metals exhibit a unique magnetic behavior which is called ferromagnetism, or the ability to hold a magnetic field. 29) What is produced by moving a permanent magnet through a coil of copper wire? A) electricity B) electromagnet C) light D) radiation None of the E) above Explanation: Electricity is produced by turning a magnet through a coil of wire. This causes current to flow through the wire. This device is called a generator. 30) A strand of 10 lights is plugged into an outlet. How can you determine if the lights are connected in series or parallel? Unscrew one If the other lights stay on, A) it's a series circuit. Unplug the strand. If the first light stays B) on, it's a series circuit. Unscrew one light. If the other lights turn off, C) it's a series circuit. Cut the strand in half. If the plugged in half D) on, it's a series circuit. None of the E) above Explanation: The correct answer is Unscrew one light. If the other lights turn off, it's a series circuit. Series circuits only provide one path for the flow of electricity. Removing a light removes that path.
Explanation: The best material to use for the core of a electromagnet is iron. Iron, nickel, cobalt and some of the rare earths metals exhibit a unique magnetic behavior which is called ferromagnetism, or the ability to hold a magnetic field. 29) What is produced by moving a permanent magnet through a coil of copper wire? A) electricity B) electromagnet C) light D) radiation E) None of the above Explanation: Electricity is produced by turning a magnet through a coil of wire. This causes current to flow through the wire. This device is called a generator. 30) A strand of 10 lights is plugged into an outlet. How can you determine if the lights are connected in series or parallel? A) Unscrew one If the other lights stay on, it's a series circuit. B) Unplug the strand. If the first light stays on, it's a series circuit. C) Unscrew one light. If the other lights turn off, it's a series circuit. D) Cut the strand in half. If the plugged in half on, it's a series circuit. E) None of the above Explanation: The correct answer is Unscrew one light. If the other lights turn off, it's a series circuit. Series circuits only provide one path for the flow of electricity. Removing a light removes that path.
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