Unit 8 Making Use of Electricity

Topic

Constructing complete circuit

Curriculum Link

8.1 Closed circuit

Estimated Lesson Time

80 minutes

Introduction

Students are engaged to focus on the concept of closed circuit by lighting up a bulb with one battery and only one wire. In order to facilitate the communication effectively, drawing circuit diagram is introduced. Then, students are required to complete two more tasks in this activity. While students are required to explore the requirements for a closed circuit in Task 2, students are guided to compare the circuits in parallel and in series in Task 3. In this activity, teacher is encouraged to use "Predict-Observe-Explain" strategy to develop students' reasoning power.

Key Question

How can we construct a complete circuit to light up a bulb?

Learning Objectives

In this activity, the students should be able to

  1. explain and test their ideas regarding different connections of circuits (SP3);
  2. illustrate with experiments that a source of electrical energy and a closed circuit are required for current flow;
  3. acquire skills in using common circuit symbols in drawing circuit diagrams (SP6 );
  4. acquire some skills in wiring simple circuits (SP5).

Teaching Plan

Task (Time) Brief Description Materials Objectives

Engagement & Exploration
(10 min)

Students are engaged to focus on the concept of closed circuit by asking students to design how to light up a bulb with 1 battery , 1 bulb and 1 wire. Students should be invited to explain their designs with the use circuit diagrams. Then, students conduct experiment to test which connections can light up the bulb.

 (1), (2) & (3)

Elaboration & Explanation
(40 min)

Task 2: Students explore the concept of closed circuit

  1. Students are asked to draw circuit diagrams for different connections of electric components. In addition, they are also asked to predict the behavior of   the bulb.
  2. Ask students to test their predictions by providing them with battery, bulbs, few wires and a switch.
  3. Invite students to explain the requirements for current flow.
  • Worksheet

  • 1 battery, 1 bulb, 1 switch, 3 wires

 (2), (3) & (4)

Elaboration & Explanation
(30 min)

Teacher explains the wiring of series and parallel circuit.

Task 3 : Comparing the circuit in parallel and in series

  1. Ask students to identify the parallel and series circuit.
  2. Invite students to predict and explain which connection will light up the bulb more brightly.(P)  
  3. Ask students to connect these two circuits to verify their predictions. (O)
Invite students to compare the circuits connected in parallel and in series. Teacher explains the brightness of bulb in term of the energy delivered from the battery. (E)
  • Worksheet

  • 1 battery, 2 bulbs, 1 switch, Few wires

 (2) & (3)

Apparatus and materials required: