Chapter 1: Electricity and Magnetism Flashcards
(24 cards)
What is static electricity?
Static electricity is created by rubbing insulators together, transferring electrons and giving the objects magnetic charges.
What is resistance?
Resistance is a measure of how easy it is to pass through a component.
What is the unit for resistance?
The unit for resistance is the ohm (Ω).
What are conductors and insulators in terms of resistance?
Conductors have low resistance, while insulators have high resistance.
What are the two poles of a magnet?
Magnets have north and south poles.
What happens when opposite poles of magnets are brought together?
Opposite poles attract each other.
What happens when the same poles of magnets are brought together?
The same poles repel each other.
What is a magnetic field?
A magnet has a field around it, which can be observed with a compass or iron filings.
How can you tell the strength of a magnetic field?
If the lines are close together, the field is stronger.
What are electromagnets?
Electromagnets are only magnetic when they have a flow of current and can be turned off.
How are electromagnets made?
They are made by running a current through a coil of wire, usually with an iron core.
How can you make an electromagnet stronger?
You can make it stronger by adding more turns of wire on the coil or using more current.
What is current?
Current is the amount of charge flowing per second.
How is current measured?
Current is measured with an ammeter, which is connected in series.
What is the unit for current?
The unit for current is the amp (A).
What is potential difference?
Potential difference is the amount of energy transferred by the charges in the circuit.
How is potential difference measured?
It is measured with a voltmeter, which is connected in parallel.
What is the unit for potential difference?
The unit for potential difference is the volt (V).
What is a series circuit?
In a series circuit, all components are connected in one loop; if one component breaks, current stops flowing everywhere.
What are the characteristics of a series circuit?
Series circuits contain only one loop, the current is the same everywhere, and the potential difference across each component adds up to the potential difference across the battery.
What is a parallel circuit?
A parallel circuit contains multiple branches, and the potential difference across each component is the same as the potential difference across the battery.
What are some uses of electromagnets?
Electromagnets are used for moving cars, sorting metals, making motors and speakers, and creating levitating trains.
How do motors work?
Applying a current to a coil of wire makes it electromagnetic, causing a force between the coil and a nearby permanent magnet, driving the motor.
