Unit 1 Introducing Science

Topic

Energy loss in collision

Curriculum Link

1.4 Conducting a simple scientific investigation

Estimated Lesson Time

80 minutes

Introduction

In this activity, the concepts of "repeat measurement" and "fair test" in scientific investigation are introduced to students. With a video clip showing the bouncing motion of a football in rainy day, teacher explains the change of energy in the bouncing motion and relates the energy stored in the ball to its bouncing height.  This activity is consisted of two tasks. Firstly, students conduct two experiments to explore the energy loss in bouncing motion of a table tennis ball and a tennis ball on different surfaces respectively. Based on the results obtained from these two experiments, students are asked to draw conclusion regarding energy loss. Secondly, students are given experiment data to analyse and draw conclusion with the concept of a fair test.

Key question

What is a fair test?

Learning Objectives

In this activity, the students should be able to

  1. recognize that energy may change from one form to another;
  2. understand that energy will lost in collision;
  3. conduct an experiment to explore the energy losses in collisions (SP3);
  4. analyse and interpret data to draw a conclusion (SP5);
  5. acquire communicating skills (SP6).

Teaching Plan

Task (Time) Brief Description Materials Objectives

Engagement
(10 min)

Students are engaged to focus on energy loss of football in collision on playground by watching a video clip. Teacher asks students to explain why the footballers cannot perform properly in the match.

Teacher asks students to notice the bouncing height of the footfall on playground of different conditions.

 (1)

Explanation
(15 min)
  • Teacher explains kinetic energy, potential energy of the football and energy loss in the bouncing motion of the football.
  • Discuss with students the change of energy of a ball when it bounces up, including energy loss in the collision with surface.
 (1) & (2)

Exploration
(40 min)

Task 1 : Students are asked to explore the energy loss of a table tennis ball and table tennis while colliding on soft or hard surfaces respectively.

(2), (3) & (5)

Elaboration
(15 min)

Students elaborate more on the design of a fair test.

Task 2 : Designing a fair test.

Some experimental results are given to students. Discuss with students to draw conclusion about energy loss in collision from the data given and hence ask students to state the requirement of a fair test.

(2) & (4)

*Apparatus and materials required: