1. The message for time has been moved to the center.
2. You can enter [b]scale[/b] by enter numerical value, so you can change the range for x and y to any value you want.  (how ever you need to adjust other parameters so that the scale make sense).
3. The max value can be change to 300 only when scale is set to larger than 20.
(from 0.01 to 300 is a very large ratio, it does not make sense for large sigma with small range).
4. The yscale for Gaussian function change according to bounce wall in the y-direction.

Click the eye (image) to display the simulation
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/htdocs/ntnujava/ejsuser/2/users/ntnu/fkh/changeGaussianField6_pkg/changeGaussianField6.propertiesFull screen applet or Problem viewing java?Add http://www.phy.ntnu.edu.tw/ to exception site list
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$a=\frac{d\vec{v}}{dt}=\frac{d^2\vec{x}}{dt^2}= \frac{q \vec{v}\times\vec{B}}{m}$
unit for t is $\mu s=10^{-6}$ , for q is $10^{-19}$C,  for m is $10^{-26}$kg, for v is km/s$=10^3$m/s, for B is T.
So the unit for x or y is $\frac{[q][v][ B ]}{[m]}[T^2]=\frac{10^{-19}\, 10^3 \, 1}{10^{-26} } 10^{-12}=10^{-2}$m=cm.
For the default setting: m=$10^{-26}$kg, q=$1.6*10^{-19}$C, v=0.2 km/s, B=1 T
$r\approx \frac{m v}{qB}=\frac{10^{-26} 0.2*10^3}{1.6*10^{-19}*1}=\frac{0.2}{1.6}10^{-4}=0.12*10^{-4}$ (m)