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# Lab- Response Time

Extracts from this document...

Introduction

Response Time Aim: To investigate whether the age of a human affects the reaction time. Introduction: Reaction time refers to the response of an organism to a stimulus, i.e. a factor leading to an organism reacting in some way. The average reaction time for a human is 0.200 to 0.250 seconds. This difference in reaction time varies from person to person due to various factors such as Age, Gender, Time, Environmental conditions, etc. Age being the most suitable factor, was chosen for the experiment. A stimulus is detected by the eye and is transmitted to the brain in the form of a nerve impulse. This impulse is interpreted by the brain which sends another impulse to the muscles in order to respond appropriately. This process is slow for aging people as well as humans below the age of 10 while are comparatively faster for people in the age group of 10-25. ...read more.

Middle

Instruct the person to hold his fingers apart in a U shape, i.e. the thumb and index while folding the other fingers 6. Hold the ruler loosely with the 0cm marking just at the same level of the thumb. 7. Leave the ruler and instruct the person to grasp it as soo as he sees it drop. 8. Observe the distance between the beginning of the ruler and the place the ruler is held and record the result in the results table. 9. Redo steps 5-8 10 times for the same person and record results. 10. Find the average of the 10 results and use the obtained value to find the "reaction time" using the conversion graph. 11. Redo steps 5-10 for all the people chosen. Results Results table 1 Reading Distance Caught(cm) 8 years 16 years 32 years 1 18 cm 18 cm 27 cm 2 20 cm 18 cm 24 cm 3 29 cm 20 cm 26 cm 4 27 cm 22 cm 25 cm 5 ...read more.

Conclusion

fastest reflexes. Evaluation: The results obtained were reliable and helped me prove my hypothesis correct. However, there were no major anomalies observed but a few minor inaccuracy errors. * The experiment conducted was manual and therefore conducted various manual errors such as inaccurate distance measured. * Another manual error could be that of not holding the ruler's 0cm mark accurately at the edge of the thumb. * The time of the day gradually increased as the experiment was conducted and therefore could not be kept as controlled variable. * The person conducting the experiment gradually got used to the act and therefore would respond better. * The ruler being a length of 30 cm, often was to small a reaction distance and therefore slipped out of the hand thereby giving no result. Improvements - If I was to conduct the experiment again, I would:- * Use a digital method to investigate the reaction time, eg- Car Brake simulation. * Use a larger number of results resulting in an increase in the accuracy of my results. ?? ?? ?? ?? ...read more.

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## Here's what a star student thought of this essay

4 star(s)

### Response to the question

A very well done experiment which shows thought behind how the experiment is going to be conducted accounting for any errors that may occur and therefore affect the validity of the experiment

### Response to the question

A very well done experiment which shows thought behind how the experiment is going to be conducted accounting for any errors that may occur and therefore affect the validity of the experiment

### Level of analysis

The candidate starts with an aim for the experiment and some good background information. The candidate shows how the stimulus is processed, which would have been better aided by a diagram to show the simple neuronal pathway. The candidate also shows consideration of the different factors which could affect the experiment and attempt to account for them during the experiment. I would not use the words lesser reaction time I would use smaller reaction time. The experiment is researched well with the aid of diagrams to plot the reaction time against the drop distance and to show how the experiment is set up. The method is easy to read, but I'm not sure the experiment would be reliable as the drop distance start points would surely differ although this is accounted for to some degree. The errors and possible improvements are done well, although the candidate does not suggest many improvements to improve that particular method of experiment.

### Quality of writing

Punctuation, grammar and spelling all done to a high level of accuracy. Layout is done well with clear subheadings.

Reviewed by skatealexia 06/08/2012

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