Three resistors sit on three parallel branches of one circuit: 10 Ω, 20 Ω, and 40 Ω. Which branch carries the most current?
Two facts you already have settle it. The first: every branch has the same voltage across it, the full source voltage. The second is a bench pattern. Recall it:
A 20 Ω resistor is swapped for a 60 Ω resistor. The battery is unchanged. What happens to the current?
So the three branches differ in only one thing: their resistance. At the same voltage, more resistance means less current.
Apply that to the branches. The 10 Ω branch has the least resistance, so it carries the most current. The 40 Ω branch has the most resistance, so it carries the least current. Ranked from most current to least: the 10 Ω branch, then the 20 Ω branch, then the 40 Ω branch.
Three resistors of different sizes sit on parallel branches. How do the voltages across them compare?
Parallel branches hold 15 Ω, 30 Ω, and 60 Ω resistors. Which branch carries the most current?
Parallel branches hold 9.0 Ω, 18 Ω, and 27 Ω resistors. Which branch carries the most current, and which the least?
Every branch has the same voltage across it.
At the same voltage, the least resistance carries the most current.
9.0 Ω is the least resistance; 27 Ω is the most.
The 9.0 Ω branch carries the most current, and the 27 Ω branch carries the least.
Parallel branches hold 25 Ω, 50 Ω, and 100 Ω resistors. Rank the branches by current, most to least.
The 9.0 Ω resistor is now swapped for a 45 Ω resistor. Which branch carries the most current?
The branches are now 18 Ω, 27 Ω, and 45 Ω.
Every branch still has the same voltage, so the least resistance carries the most current.
18 Ω is now the least resistance.
The 18 Ω branch now carries the most current.
Compare the two ranking rules. In a series circuit, every component carries the same current, so the biggest resistance takes the biggest voltage. In a parallel circuit, every branch has the same voltage, so the smallest resistance carries the biggest current.
A parallel circuit has branches of 12 Ω, 18 Ω, and 36 Ω. Rank the branches by the current they carry, most to least.
Parallel branches hold 8.0 Ω, 16 Ω, and 24 Ω resistors. Which branch carries the least current?
Lamp A (5.0 Ω) and lamp B (20 Ω) sit on parallel branches. Which lamp carries more current?