Toy train

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Key Learning Points

1. position, distance and displacement
2. scalar and vector quantities
3. speed and velocity

Fig. 1 The two paths of the toy train.

Video clip: Play [Low | High]   Download [Low(333kb) | High(590kb)]

Introduction

In the video clip, a toy train travels from one point to another through two different paths. The distance, displacement and the time used are shown. Students will be asked to find the average speed and average velocity of the train for each path, and to compare the differences.

Procedures and questions

1. Sketch the two paths of the toy train on a sheet of paper. Mark the starting point as 'A' and the destination as 'B'.
2. Record the length of the paths, and the time used for travelling along the paths as shown in the video.
3. Are the distances the same for the two paths? How about the displacements?
4. Calculate the average speed of the toy train for each path. Are they the same? Why?
5. Calculate the average velocity of the toy train for each path. Are they the same? Why?