Science U
How to Test Your Reaction Time
Season 2 Episode 3 | 1m 55sVideo has Closed Captions
How fast is your reaction time? How fast does the eye send messages to the brain...
How fast is your reaction time? How fast does the eye send messages to the brain and the brain send messages to your hand muscles to react in time to catch a falling object? ScienceU campers find out using the "ruler test". If you know the rate of falling objects (9.8 meters per second squared) you can convert the distance recorded on the ruler to the speed of your reaction.
Problems playing video? | Closed Captioning Feedback
Problems playing video? | Closed Captioning Feedback
Science U is a local public television program presented by WPSU
Science U
How to Test Your Reaction Time
Season 2 Episode 3 | 1m 55sVideo has Closed Captions
How fast is your reaction time? How fast does the eye send messages to the brain and the brain send messages to your hand muscles to react in time to catch a falling object? ScienceU campers find out using the "ruler test". If you know the rate of falling objects (9.8 meters per second squared) you can convert the distance recorded on the ruler to the speed of your reaction.
Problems playing video? | Closed Captioning Feedback
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Today Science-U campers use their brains!
Well, that's a given - because Science-U campers use their brains every day!
But especially today!
Campers know that their brain controls their body - through the central nervous system.
But how fast does the brain send messages to the body?
We're going to measure Science-U camper's reaction time - with the ruler test!
The ruler test?
The ruler test!
You stand over the test subject with the ruler - and put the end of the ruler right between his opened fingers - Then, without telling him when you're going to do it... Should I drop it?
you drop the ruler!
And I have to catch it!
We measure the distance on the ruler by recording where he grabbed it.
4 and a half inches!
The further it fell - the slower the reaction!
18!
The ruler is falling at 9.8 meters per second squared.
We can do the math and chart the reaction time!
I was fast...
I was faster!
No you weren't - Yes I was - Lets examine how the brain and the body work together!
Our eyes see the ruler's been dropped.
Ruler's been dropped!
Dropped!
Dropped!
Signals race through sensory neurons to the brain.
Message received!
Grab it!
The brain then fires off the message through motor neurons down the arm-- - Grab it!
-- - to tell the hand to catch the ruler.
Mission completed!
Your reaction time depends on your eyesight and the speed that the signals travel to your brain and from your brain to your muscles.
So what do you want to test next?
Right hand versus left hand.
I want to try it on my Dad!
How fast is YOUR reaction time?
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Science U is a local public television program presented by WPSU