Science Unit 2.5 Flashcards
What is a circuit
Circuit is a continuous loop consisting of an energy source, conducting wires, one or more loads, and a switch
What is a series circuit
A circuit that has only one pathway from the current to flow.
What is a parallel circuit
A circuit that has two or more paths for current to flow
What is an electric current
Electric current is the rate of electron flow past a specific point in a current
What is the unit of measurement and symbol for electric current
The unit of measurement=Ampere (A)
Symbol= I (uppercase i)
What is a ammeter and what is specific about it
An ammeter is an instrument for measuring electric current in amperes. It must be connected in SERIES with a load to measure the current flowing through the load
What is potential difference (voltage)
The difference in the amount of energy that charge carries, like a wire or load, have between two points in a circuit
What is the unit of measurement and symbol for voltage
The unit for voltage is the volt (v)
How to measure voltage
Voltmeter is a device to design to measure the potential difference. Unlike an ammeter, a voltmeter must be connected to a parallel circuit with a load or an energy source.
What is resistance
Electrical resistance is the opposition to the movement of electrons as they flow through a circuit .
What is the unit of measurement and symbol for resistance
Symbol=R
Unit of measurement= Ohm (Ω)
What are the factors that affect resistance
- Types of Materials
- Cross-sectional Area
- Length
- Temperature
Types of materials
The ability of a material to conduct electricity is determined by health really electrons can move within the material.
Cross-Sectional Area
Electrons flowing through a thicker wire, have more room to move freely compared to thinner wires
Length
As you increase the length of a wire, it’s internal resistance increases. This happens because electrons have to travel through more materials.
Temperature
At higher temperatures, atoms vibrate and move around more. Resistance increases when electrons bump into atoms as they move through a material.
What is a resistor
A resistor is an electrical device that reduces the current in a circuit
