GRADE 7 – LAB 5: Electric circuits

Aula prática 11 de agosto de 2026

ESSENTIAL QUESTION:

What does an electrical circuit need to work?

HYPOTHESIS:

Write your statement using “if… then… because…” form.

OBJECTIVE:

Investigate how electrical circuits work by constructing and testing simple circuits, identifying the conditions necessary for electric current to flow.

MATERIALS:

For each group:

  • 1 or 2 batteries
  • 1 battery holder
  • 2–3 connecting wires
  • 1 small light bulb and bulb holder
  • 1 switch
  • Objects made of different materials for testing:
    • metal paper clip
    • aluminum foil
    • coin
    • plastic ruler
    • wooden stick
    • rubber band

SAFETY RULES

  • Use batteries only.
  • Never connect the two terminals of a battery directly.
  • Do not touch or modify the battery.
  • Disconnect the circuit when you are not testing it.
  • Handle the bulb carefully.

PROCEDURES:

PART 1 — MAKE THE BULB LIGHT

Procedures:

  1. Place the battery in the battery holder.
  2. Connect one terminal of the battery to the bulb holder.
  3. Connect the bulb holder to the switch.
  4. Connect the switch back to the other battery terminal.
  5. Close the switch.
  6. Observe what happens.

PART 2 — BREAK THE CIRCUIT

Now open the switch. What happened?

RESULTS

COPY THE PHRASES BELOW AND REGISTER ON YOUR SCHOOL PAPER WHAT YOU DISCOVERED.

When the switch is closed, the circuit is ____________________.

When the switch is open, the circuit is ____________________.

Introducing the scientific terms:

CLOSED CIRCUIT

A complete conducting pathway that allows electric current to flow.

OPEN CIRCUIT

A circuit with a break in the pathway that prevents electric current from flowing through the complete circuit.

DISCUSSION:

Copy and complete the sentences using the correct vocabulary:

battery — current — conductor — insulator — open — closed

  1. The battery provides the energy that drives the electric ____________.
  2. A metal paper clip is a good electrical __________________.
  3. Plastic is generally an electrical __________________.
  4. When the switch is closed, the circuit is __________________ and current can flow.
  5. When the switch is open, the circuit is __________________ and current cannot flow through the complete pathway.

Now represent your working circuit using a simple circuit diagram.

Draw and label:

  • Battery
  • Wires
  • Bulb
  • Switch

CONCLUSION:

Copy and complete the paragraph:

In this investigation, we learned that an electrical circuit needs a __________________ pathway for electric current to flow. When the switch is closed, the circuit is __________________ and the bulb lights. When the switch is open, the circuit is __________________ and the bulb does not light.

We also discovered that materials such as __________________ are good conductors, while materials such as __________________ are insulators.

Based on what we learned, we can use a circuit to create a device that detects when ________________________________.