2.1 introduction to motion

• P&C
• Middelbare school
• vwo
• Leerjaar 2

Chapter 2: Motion

Taboo

1. Without telling anyone, think of a type of movement or transport.

2. Write down your idea in the centre of the piece of paper which is given to you and circle it.

3. Think of three words you are not allowed to use to describe your idea and put them on the piece of paper as well.

4. Hand in the papers without showing them to anyone.

5. After you get one back, try and describe the Taboo word (in English ofcourse) without using any of the words on the paper.

Motion in sports and traffic

Capturing movement

Sometimes it is really important to capture movement going on, in races, all sorts of tests (like practicals) and comparison of all sorts. You need to capture the entire motion, not only the result so you can analyse it piece by piece and use it to enhance future performances

How to capture motion

You can capture motion on video or on special photographs, in which multiple frames are put into one photo (a stroboscopic photo)

When you use video the framerate (the amount of pictures each second) needs to be quite high, dependent on what you want to capture (race video's are in a framerate of thousands)

using stroboscopic photos

You need to have a scale in the photo or a ruler of sorts to use for exact distance and speed measurements.

A stroboscope has a certain frequency of flashes (the amount of flashes each second) Each photo of the object you see is taken with one of those flashes, the rest of the time it is completely darkened. The first flash gives you the starting point at 0 seconds. So make certain you don't count the first flash in your time calculations

If the stroboscope has a frequency of 2 (0,5 seconds between flashes) what is the time when the ball reaches the highest point in the picture?

Tables and graphs

You will work with tables and graphs during this chapter.

You will make them or consult them for information about the movement of objects and/or people. This is another way of capturing and analysing movement. You will find graphs with the distance and the time (x,t-diagram) , but you might also find graphs with speed and the time (s,t-diagram) , so look carefully what a graph is about.

Read paragraph 2.1

Do exercises 1, 2, 3, 4, 5, 9, 10, 12