Open and Closed Circuits Worksheet - Free Printable

Let’s go through each circuit one by one. Remember:

- A closed circuit means the path is complete — electricity can flow, and bulbs will light up.
- An open circuit means there’s a break in the path — electricity cannot flow, so bulbs won’t light.

We look for gaps (like open switches) or broken paths. If everything is connected with no breaks, it’s closed.

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Circuit 1:
There’s a battery, two dots (which might be connection points), and a bulb. The line goes all the way around — no gap. Even though there are two small circles on the left, they’re part of the wire path. So this is a closed circuit.

Wait — actually, looking again: those two small circles on the left side — if they’re meant to represent an open switch or disconnected point, then it would be open. But in standard diagrams, if there’s no switch symbol shown as “open”, and the lines connect fully, we assume it’s closed. However, in many worksheets like this, those two small circles often mean an open switch (like a gap). Let me check common conventions.

Actually, in most elementary circuit diagrams:
- A switch that is drawn with a gap = open
- A switch drawn as a solid line = closed
- Two separate dots with no line between them = open

In Circuit 1, on the left side, there are two small circles with no line connecting them — that’s a gap! So the circuit is broken there → open

But wait — let me double-check. In some diagrams, those could just be junctions. But since there’s no wire connecting them vertically, and they’re placed where a switch might be, it’s likely intended to show an open switch.

Looking at other circuits for comparison:

Circuit 2 has a clear open switch (a diagonal line not touching) → definitely open.

Circuit 4 has two dots on the left with no connection → same as Circuit 1? Then both should be open.

Actually, let’s use a consistent rule:

→ If you can trace a continuous path from the positive terminal of the battery, through all components, back to the negative terminal, without any gaps — it’s closed.

If anywhere along the path there’s a break (no wire, or switch open) — it’s open.

So let’s apply that strictly.

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Circuit 1:
Start at battery (+), go down → hit first dot → but no wire going up to second dot → so path is broken → open

Circuit 2:
Battery → bulb → then a switch that’s clearly open (diagonal line not connected) → so path broken → open

Circuit 3:
This is a parallel circuit. Battery connects to three branches. Each branch has a bulb or switch. Look at the bottom row: there’s a switch that’s open (gap), and another set of dots with no connection. Actually, tracing carefully:

From battery (+), splits into three vertical paths.

Left path: bulb → then wire continues down to bottom horizontal wire.

Middle path: bulb → then a switch that’s open (so that path is broken).

Right path: just wires and dots — but the dots aren’t connected? Wait, in the rightmost branch, there are three dots in a row with no wires between them? That doesn’t make sense. Probably it’s meant to be a switch or connector.

Actually, looking again — in Circuit 3, the bottom horizontal wire connects all three branches. But in the middle branch, after the bulb, there’s a switch that’s open — so current can’t go through middle branch. But the left branch has a bulb and is connected — so current can go through left branch and return. Also, the right branch — if the three dots are meant to be connected (maybe it’s a typo or misdrawn), but as drawn, if there’s no wire between the dots, then right branch is also open.

But here’s the key: even if one path is complete, the whole circuit can still work (in parallel). So if at least one path is closed, the circuit is considered closed? No — actually, the question is about whether the *entire* circuit allows current to flow. In parallel circuits, if one branch is open, others can still work. But the overall circuit is still “closed” if there’s at least one complete path.

However, in basic school-level questions, they usually consider the circuit “closed” only if all parts are connected properly — but that’s not accurate technically.

Wait — let’s think simply: does current have a complete loop from battery + to -?

In Circuit 3:

Path 1 (left): battery + → top wire → left bulb → bottom wire → battery - → YES, complete.

Even though middle and right branches may be open, the left branch works → so current flows → circuit is closed

But is that correct? Yes — in real life, if one branch is open in parallel, the rest still work. So the circuit is functional → closed.

But let’s see what the worksheet expects. Often in these diagrams, if there’s any open switch or gap, they mark it as open — but that’s wrong for parallel circuits.

To avoid confusion, let’s look at the diagram again.

In Circuit 3, the bottom horizontal wire connects all three lower ends. The top horizontal wire connects all three upper ends. So:

- Left branch: bulb only → connected → good.
- Middle branch: bulb + open switch → so that branch is open.
- Right branch: three dots — if they are meant to be connected, it’s fine; if not, it’s open. But since there are no lines between them, probably it’s intended to be open.

But again, since left branch is complete, current can flow → circuit is closed.

I think for this level, they might expect us to say "closed" if there's any complete path.

But let’s check online or standard answers — no, I need to decide.

Alternative approach: in many such worksheets, they consider the circuit open if there is ANY break in the main path — but in parallel, there isn't a single main path.

Perhaps for simplicity, we should look for whether the battery is connected in a loop with no gaps.

In Circuit 3, from battery + to top wire, then to left bulb, to bottom wire, to battery - — that’s a full loop with no gaps → so closed

Yes.

Circuit 4:
Battery → then on the left, two dots with no wire between them → gap → so path broken → open

Also, there’s a bulb at the bottom, but since the left side is open, no current flows.

Circuit 5:
Battery → then a switch that is closed (solid line) → then two bulbs in series → back to battery. All connected → closed

Circuit 6:
Battery → switch that is open (diagonal line not connected) → then two bulbs in parallel. But since the switch is open before the parallel branches, no current reaches them → so entire circuit is open

Now summarize:

1) Open (gap on left)
2) Open (switch open)
3) Closed (left branch complete)
4) Open (gap on left)
5) Closed (all connected)
6) Open (switch open at start)

But let me confirm Circuit 3 once more.

In Circuit 3, is the left branch really complete? From battery + to top wire, down through left bulb, to bottom wire, to battery - — yes, no gaps. The other branches don’t affect this path. So yes, closed.

Some might argue that the dots in the right branch indicate a problem, but since we don’t need that branch for current to flow, it’s fine.

Final decision:

1) Open
2) Open
3) Closed
4) Open
5) Closed
6) Open

Now, write the answer.

Final Answer:
1) open
2) open
3) closed
4) open
5) closed
6) open