Nothing Uses Up Current

You'll learnwhat a circuit conserves and what it spends: the same current everywhere in one loop, energy dropped only at the bulbs, and a battery that fixes voltage while the circuit decides the current.

Two identical bulbs share a loop with a 12 volt battery, and they glow exactly the same, because nothing on the way round uses up current. What each charge spends is energy, and the battery never decides how much current flows: the circuit does. Twelve short steps; press Next for each one.

12 STEPS · 6 QUICK CHECKS · ONE CURRENT · VOLTS ARE SPENT · THE CIRCUIT DECIDES · v2

one loop · nothing uses up current · volts are what get spent

Before you start

What you're looking at

A 12 V battery and two identical bulbs in one loop. The dots riding the wire are charge on the move.

The question

Going once around the loop, what stays the same, and what gets spent?

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