Reaction Timer


In this problem, you will meet two different ways to test your reactions.

This reaction timer will enable you to collect data on the time it takes you to respond to an image on your computer.

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Note: You can copy/paste the results table into a spreadsheet

Here is a second experiment you can use to test your reactions.
Ask a friend to hold a ruler by the end, above your hand. Open your hand below the ruler and be ready to catch it. Your friend will drop the ruler without saying when they're going to let go. Catch the ruler as fast as you can after it's been dropped.
The pictures below show this experiment being carried out:

hand holding ruler

Record the level (in centimetres) at which you caught the ruler, and repeat the experiment several times. If you have quick reactions, the ruler will not have travelled far when you catch it.

Taking only one measurement in either of these experiments will not give you a reliable, accurate measure of speeds of reaction that could be used to rank a group of people.

Decide how many measurements you will take, and what you will do with them to provide an accurate measure of reaction speeds. Make sure you can justify your decisions.

Here are some questions you might like to consider:

Test any hypotheses you come up with.

You may also wish to explore how accurately you can estimate time.