Which statement correctly describes the main difference between series and parallel circuits?

Which statement correctly describes the main difference between series and parallel circuits?

• A. In a series circuit, current is the same through all components; in a parallel circuit, voltage is the same across all branches.
• B. In a series circuit, both voltage and current are the same across all components.
• C. In a parallel circuit, current is the same through all branches; voltage varies.
• D. Only series circuits allow current flow; parallel circuits do not.

Answer: (A)

The main idea is how current and voltage behave differently in one path versus multiple paths. In a series circuit there is only a single path for current, so the same current flows through every component; the total supply voltage is split among the components and the voltages add up to the source. In a parallel circuit there are multiple paths, so the voltage across each branch is the same as the source, while the currents in each branch can differ and add up to the total current. This matches the statement: the current is the same through all components in a series circuit, and the voltage is the same across all branches in a parallel circuit. The other descriptions run counter to how current and voltage distribute in series and parallel networks.

The main idea is how current and voltage behave differently in one path versus multiple paths. In a series circuit there is only a single path for current, so the same current flows through every component; the total supply voltage is split among the components and the voltages add up to the source. In a parallel circuit there are multiple paths, so the voltage across each branch is the same as the source, while the currents in each branch can differ and add up to the total current.

This matches the statement: the current is the same through all components in a series circuit, and the voltage is the same across all branches in a parallel circuit. The other descriptions run counter to how current and voltage distribute in series and parallel networks.