Scalectrix Experiment.

Light gate

Scalectrix track

Scalectrix car

Variable resistor

Ammeter

Crocodile clips

Wire

Solder and soldering iron

Wire clippers

Clamps

Stand

I will set up my apparatus as shown in the diagram below

What I am going to measure, count and observe

I'm going to measure, the current using an ammeter and the speed of the car at three points using an electronic timer. I also measured the distances of the light sensors from the start.

To make it a fair test I will have to

I will carry out preliminary experiments to find out

By producing preliminary experiments it can show if my theory works as well as my method.

These are the results of my preliminary experiment

Length of Card

6.50

Current in Amperes

Time 1 in ms

Time 2 in ms

Time 3 in ms

Speed 1

Speed 2

Speed 3

0.24

25.14

9.62

20.50

2.59

3.31

3.17

0.20

23.53

8.38

8.06

2.76

3.54

3.60

0.16

30.52

24.50

27.99

2.13

2.65

2.32

0.12

48.48

39.85

42.19

.34

.63

.54

I now know to do this experiment I must

To do this experiment I must accurately take readings and set up my apparatus quickly so there is anough time to carry out my practical.

This is the table in which I will record my results

Length of Card

Current in Amperes

Time 1 in ms

Time 2 in ms

Time 3 in ms

Speed 1

Speed 2

Speed 3

Here is a table with the results of my experiment

Length of Card

6.50

Current in Amperes

Time 1 in ms

Time 2 in ms

Time 3 in ms

Speed 1

Speed 2

Speed 3

0.24

25.14

9.62

20.50

2.59

3.31

3.17

0.24

24.37

9.10

8.82

2.67

3.40

3.45

0.24

22.82

8.18

7.73

2.85

3.58

3.67

0.20

23.40

9.11

8.22

2.78

3.40

3.57

0.20

23.53

8.38

8.06

2.76

3.54

3.60

0.20

23.52

8.43

8.06

2.76

3.53

3.60

0.16

31.47

25.82

26.10

2.07

2.52

2.49

0.16

31.63

24.86

26.44

2.06

2.61

2.46

0.16

30.52

24.50

27.99

2.13

2.65

2.32

0.12

48.48

39.85

42.19

.34

.63

.54

0.12

50.96

42.21

42.91

.28

.54

.51

0.12

53.25

41.94

41.09

.22

.55

.58

In addition I have made the following observations

In addition to the first experiment we did we tried the same thing with weights on top of the cars. This was quite interesting because the car didn't become any faster but it was more powerful. In one case with the heaviest weight we put on, the car went much slower yet when it hit the barrier we made at the end of the track for the cars to crash in to, it made the barrier go flying. I think this relates to the equation FORCE=MASS?ACCELERATION.

I have drawn a graph of my results I have found out that

The higher the current in amperes the quicker the time meaning the car will travel faster.

I know from my background reading that

The more current it has the faster the car will go.

My results relate to my knowledge as follows

My results relate to my knowledge because the cars got faster as we increased the current.

My results agree with my original prediction in the following way

My results agree with my prediction because the car got faster as the current increased. For example we started with the current at 0.24 and the speed was 2.59. Then we made the car decrease in speed to a current of 0.12 and the speed was 1.22.

I think my results are accurate because

I think my results are accurate because they agree with my prediction, and the graph was a good reliable shape.

Overall I think are reliable because

I think my results are reliable because, they coincide with my original prediction, they agree with my research and they make a good graph.

I think I have sufficient evidence to support my conclusion because

I think I have sufficient evidence because the graphs show an obvious trend. I.e. the higher the current, the faster the time. The higher the current, the higher the speed.

To make my results better I could improve the method used as follows

To make my results better I could take more readings on one piece of track instead of just three. I could also take them more often for each value of the current. We could also put weights on the car and see what happens.

I could obtain further evidence

I could obtain further evidence by researching on the Internet and persisting with more experiments.

I could extend my enquiry

I could extend my enquiry by doing an experiment using a toy petrol engine to see how the speed depended on the setting of the supply throttle.