simple circuits (P3.2) Flashcards
What is Potential Difference?
A difference in (electrical) potential produced by the separation of charge; a potential difference produces an electrical field which produces a force on charged particles in it
What do you need to make a current flow?
potential difference
What does potential difference and current depend on?
The construction and not the size
What is potential difference measured in?
Volts (V)
On a cell symbol what does the loner and shorter line mean?
Longer line is positive and the shorter line is negative
How do you set up an electrical field?
Apply a p.d between the ends of a piece of a wire
How do you measure potential difference
Voltmeter
What is the electrical working
When you connect a voltmeter across a component in the circuit you measure the work done or energy transfered by the charges in the component.
What is the formula for charge?
Charge= Energy/P.D
How do you measure current
ammeter
Why should ammeters be in a loop?
Because charge needs to flow through them
What 2 things can a voltmeter measure?
rise in potential
drop in potential
What does current depend on?
The current in a circuit depends on the potential difference of the cell or battery and the resistance of the components.Resistance is measured in ohms
What is the equation for current (A)
Current=P.D/Resistance
When is resistance produced?
When electrons collide with the ions in the lattice
