The amount of current is the same through any component in a series circuit. Resistance: The total resistance of any series circuit is equal to the sum of the individual resistances. Voltage: The supply voltage in a series circuit is equal to the sum of the individual voltage drops.
Answer:
= 40 cm
Explanation:
given data
string length = 30 cm
solution
we take here equation of length that is
L =
...............1
so
total length will be here


so
will be

= 40 cm
The first and third choices on the list will attract, because UNlike poles are facing across the gap.
Choice #1: . . . [S]-----[N] . . . [S]-----[N]
Choice #3: . . . [N]-----[S] . . . [N]-----[S]