This worksheet challenges students to analyze Circuit 1 (series) and Circuit 2 (parallel) to determine if the bulbs will glow under different conditions.

Let’s go step by step through both circuits.

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Circuit 1:

This is a single loop with a battery, a switch, and three lamps (A, B, C) all connected one after another. That means it’s a series circuit.

In a series circuit:
- If the switch is OPEN → no current flows → nothing works.
- If any bulb is broken (burnt out), the whole circuit breaks → no other bulbs glow.
- All bulbs must be working AND the switch closed for anything to glow.

Now let’s answer each question:

1. Is it a series or parallel circuit?
→ Series — because there’s only one path for electricity to flow.

2. In its current condition (switch open), will the bulbs work? Why?
→ No — because the switch is open, so electricity can’t flow at all.

3. The switch is now CLOSED. Will the bulbs work? Why?
→ Yes — if all bulbs are good, closing the switch completes the circuit, so current flows and all bulbs glow.

4. Switch CLOSED. Lamp A is broken. Lamps B and C will:
→ Not glow — because in series, one broken bulb breaks the whole circuit.

5. Switch CLOSED. Lamp B is broken. Lamps A and C will:
→ Not glow — same reason. One break stops everything.

6. Switch CLOSED. Lamp C is broken. Lamps A and B will:
→ Not glow — again, series circuit = one failure kills all.

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Circuit 2:

Here, each lamp (A, B, C) has its own separate path from the battery. They’re side-by-side. This is a parallel circuit.

In a parallel circuit:
- Each branch works independently.
- If one bulb breaks, the others still get power and glow.
- Even if two break, the third can still work — as long as the main wire isn’t broken.

Now the questions:

1. Is it a series or parallel circuit?
→ Parallel — because each lamp has its own path to the battery.

2. In its current condition, will the bulbs work? Why?
→ Yes — assuming no bulbs are broken and wires are fine, all paths are complete, so all bulbs glow.

3. Lamp A is broken. Lamps B and C will:
→ Glow — because they have their own paths; breaking A doesn’t affect them.

4. Lamp B is broken. Lamps A and C will:
→ Glow — same logic. Independent paths.

5. Lamp C is broken. Lamps A and B will:
→ Glow — again, parallel circuits don’t depend on each other.

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Final Answer:

Circuit 1:
1. Series
2. No — switch is open, so no current flows
3. Yes — switch closed completes the circuit, all bulbs glow if working
4. not glow
5. not glow
6. not glow

Circuit 2:
1. Parallel
2. Yes — all branches are complete, so all bulbs glow
3. glow
4. glow
5. glow