P3.1.2 - Electric Current Flashcards
What is current?
The rate of flow fo charged particles
What are charges made of?
Electrons
What do you need to make a current flow?
A cell, battery or power supply
A complete circuit
Where is the current largest in a single closed loop?
Nowhere, as it is equal throughout the loop
When you draw the direction of electric current on a circuit diagram, which direction should you draw it?
From the positive terminal to the negative terminal. This is called conventional current
What is the opposite of a conventional current?
Electron flow
What is charge measured in?
Coulombs, clusters of electrons
How many electrons are in a Coulomb?
6.25x10 to the power of 18
What is current measured in?
Amperes (amps)
What are small currents measured in?
Milliamperes
What is the equation for charge flow?
Charge flow = current*time
How can you calculate the current?
Current = charge flow/time
What is the formula for resistance?
Potential difference/current
What is potential difference?
A difference in potential produced by the separation of charge that enables charges to do work
Change or difference in voltage
What is resistance?
A measure of how easy it is for current to flow
