chap 7 chap stick current Flashcards
What is a galvanometer
Used to detect very small electric currents
What is electric current defined as
Rate of flow of electric charges through a conductor
How to measure electric current & SI unit
Ammeter
ampere (A)
What is voltage
Potential difference between two points
How is voltage measure + SI Unit
Voltmeter
volt (v)
In what circuit are Ammeter and Voltmeter connected respectively
A - Series
V - Parallel
Why is Ammeter connected in Series and Voltmeter in Parallel
A - To get the full current flowing through a branch
V- objects in parallel experience the same potential difference
What is resistance
Ability of a conductor to limit or resist the flow of electric current
What is the SI unit for resistance & what are types of resistor
Ohm
Fixed resistor (cannot be adjusted)
Variable resistor / rheostat (can be adjusted)
Where is rheostat used in
Radio / TV
What is the relation between current, voltage and resistance
Ohm’s Law (V=IR)
What does Ohm’s Law state
Electric current -> directly proportional -> Voltage across two ends of the conductor
Provided temperature & other physical situations remain unchanged
How does battery work
Terminal neg - excess neg
Terminal pos - lack neg
Causes potential difference & energy that pushes electron from neg -> pos
After some time, potential diff will lessen and battery dies
What is a series circuit
Made up of electrical components - connected one after another,
Current flows through single path
What is a parallel circuit
Separated into several diff parts of electrical circuit
Each parallel path has electrical components
