electricity - series and parallel circuits

Question 1

define current

Answer 1

current is the flow of charged particles
unit of electrical current - ampere (A)
you measure it using an ammeter

Question 2

define voltage

Answer 2

voltage is a measure of the difference in energy between one part of a circuit and another
unit of voltage - volts (V)
you measure it using a voltmeter

Question 3

define resistance

Answer 3

resistance is opposition to the flow of current
unit of resistance - ohms (Ω)
you measure it using a resistor

Question 4

series circuits

Answer 4

a series circuit is one loop - the current has one route to take

• the current is the same throughout each ammeter
• the total PD of the power supply is shared between voltmeters
• the total resistance is the sum of all resistors

Question 5

parallel circuits

Answer 5

a parallel circuit is multiple loops and branches

• the total current supplied is shared between ammeters
• the total resistance is less than the smallest resistance
• the potential difference is the same across all voltmeters and is the same as the voltage of the battery
• current will go where there is less resistance
• total current entering a junction = total current leaving a junction
• current at the start = current at the end

Question 6

combinations of cells

Answer 6

if cells are arranged in series, find the total PD by adding the individual PD

if a cell is connected back to front, it cancels out one of the others

if cells are arranged in parallel, the PD of the combination matches the PD of one cell. if one cell fails, the others will continue to function.