# Physics P3 General Stuff

• Created by: Aleena
• Created on: 06-05-18 20:17
What is Current & unit?
Current is the rate of flow of electric charge (electrons) around a circuit.Current only flows if there's a potential difference across that component & if the circuit is complete(closed).Unit:A (ampere)
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What is Potenial Difference & unit?
P.d also known as voltage. This is driving force that pushes the current around the circuit.Unit:V (Volt).Also,is the energy transferred per coulomb of charge
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What is Resistance & its unit?
measure of how easily charge can flow(current).Unit:ohm(look up the special unit symbol in revision guide)
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How does the p.d & resistance affect the current?
More P.D=higher current More resistance=smaller current
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What is equation for charge?Units included
Charge (C)=current(A) x time(s) Charge is measured in coulombs
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What is the equation to calculate the energy transferred per coulomb of charge?
energy transferred(J) = charge(C) x Potential Difference (V)
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What does Ammeter do?
measures the current flowing thru component.Never place parallel to voltmeter and must be placed in series
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What does Voltmeter do?
measures p.d across component e.g. light bulb.Must be placed parallel with component under test.Not with a variable resistor/battery-so it can compare the energy the charge has before & after passing thru component
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How do you calculate potential difference?
Potential difference (V) = Current (A) x Resistance (ohms)
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## Other cards in this set

### Card 2

#### Front

What is Potenial Difference & unit?

#### Back

P.d also known as voltage. This is driving force that pushes the current around the circuit.Unit:V (Volt).Also,is the energy transferred per coulomb of charge

### Card 3

#### Front

What is Resistance & its unit?

### Card 4

#### Front

How does the p.d & resistance affect the current?

### Card 5

#### Front

What is equation for charge?Units included