Reaction time measurement

[mitul009]

This is a very useful post. Thanks for sharing.

-*-

[redheadnraw]

Dr. Hwang,
There seems to be a problem with your calculator at the bottom of your post.  When I change it from km/h to m/h, the Dbrake amount stays the same, even though it should be higher because it is supposed to change from meters to feet.  This is not a huge problem, but it is probably worth fixing.  Thank you for all of your help and posts

[Fu-Kwun Hwang]

If you just change the unit, the number in front of the unit changes,too!
For example: 72km/h equal to 20 m/s, that is why the braking distance is the same.


You need to change the number in the text field (to differnt velue) to find different braking distance.

[redheadnraw]

I see that i wasn't exactly clear.  I meat from kilometers per hour to miles per hour.  Every other number in the equation shifts to become feet, but the Dbrake stays the same.  For example, if I set the calculator to read 72 kilometers per hour, the Dbrake reads 20 meters, but if I change 72 kilometers to 45 miles per hour, the Dbrake reads 20 feet.  That number should go up because feet are smaller than meters.

[Fu-Kwun Hwang]

I understand what you mean now.
The simulation allow user to change the unit for initial velocity(km/h, m/s or mile/h).
However, the braking distances and the distance due to reaction time are all expressed in meter.
The braking distance is 25.51m when the friction coefficient is 0.8

The mile/h was added due to request from one of the user, so I added that item in the selection list.
But I did not change the unit in the simulation from m to ft. That is why the number is the same, if you just changh the unit.

I just found out from the code that there are two parameters for the applet

Code:

<param name="european" value="no">
<param name="feet" value="no">

The "." in the displayed number field will be switched to "," if the value for "european" is changed to "yes".
And the unit in the simulation will be changed from "m" to "ft" if the value for "feet" is changed to "yes",too.

[Fu-Kwun Hwang]

I just modified the code (again) so that it will automatically diaplay in unit of "ft" when "mile/h" were selected, and switch back to "m" when others were selected. But the scale at the left side is not changed.

[redheadnraw]

Thank you  .  you do some good work and are prompt.  Thanks very much!

[jimmy-law]

really great effort by Fu-Kwun Hwang can i get updates on that

[Fu-Kwun Hwang]

really great effort by Fu-Kwun Hwang can i get updates on that

Do you mean that you need the source code? It is available as attached file under the first message.

You are welcomed to check out EJS verasion of Reaction time measurement

[ahmedelshfie]

Hi prof,
Error applet don't loading!

[Fu-Kwun Hwang]

I just tried it. It works fine.
It seems to be a problem from your browser.
May be you need to re-start your browser or ...?

You might want to check out EJS version of the same simulation: Reaction time measurement

[arame08]

I was the problem or rather my name. It contains an unusual Danish character (ø) and this means that when I save your applet to a folder in my documents all path-names will contain this unusual character. But the applet cannot handle unusual characters in path names. I moved the applet to the root-directory (C:\) and all problems disappeared.

[jpm1999]

Hi,
I'm trying to use your reaction time measurement applet offline but it registers as corrupt.  I have tried other jar files and they work fine.  I also downloaded it several times from different browser formats and tried opening it with different zip programs.  What can I  do?  I think the applet is great and would like to use it in class Monday.

Thanks,
Jo

[Fu-Kwun Hwang]

I just download it (Reaction.zip) without any problem.
You need to unzip it (It was fine when I unzio the file).
Then you can use browser to open ReactionTime.html or Reaction_de_xxx.html for different language version.
Please try it again!

[TONUSSARKAR]

Our goal is to both inform and entertain you with thoughts that provoke the age old question of “what if”.