Resistance Flashcards
What is resistance?
The difficulty that a charge has in moving around a circuit (resistance is measured in ohms)
What is a conductor?
A substance that allows electricity to move through it easily
What is a resistor?
A component that controls the amount of current in a circuit.
What is an LED?
A light emitting diode
What are the factors that affect resistance?
Type of material
*Copper (Low Resistance, High Current)
*Nichro (High resistance, Low current)
Length of conductor
*Long (High _ Low)
*Short (Low _ High)
Thickness of conductor
*Thick (Low _ High)
*Thin (High _ Low)
Temperature of conductor
*Hot (High _ Low)
*Cold (Low _ High)
How do you calculate resistance?
R= V/I
How do you calculate voltage?
V=IxR
How do you calculate current?
I= V/R
What is a fuse?
Used to protect the circuit and people from the heating effect of an electric current. (Consists of a thin wire that melts when the circuit gets too hot and it stops current)
What is a circuit breaker?
Electrical switches that automatically turn off the flow of electrical current when an overload or short circuit is detected
What is earth leakage?
Another safety device which becomes activated if a circuit is overloaded, the purpose of this is to protect people from injury or death. It limits the amount of current that can pass through the human body and the time for which it can pass.
