TOFMS Demo home page

Mass Spectrometry


Demo using Balls and Springs


Acceleration of ions

Electric field gives
each ion the same
kinetic energy.


Acceleration of balls

Uniform spring
compression gives
each ball the
same kinetic energy.


In this case the blue ball weighs more than the green one.

More info

The ions (or balls) all have the same energy (E),
and since

E = mv2

the lighter ones (lower m) go faster (higher v)
than the heavier ones (higher m)!


Physical Demonstration

Click on any photo to see full-size version.

See the movies!
MPEG files.




track.jpg (19176 bytes)

Complete apparatus.

pieces.jpg (15597 bytes)

Track and springs
before loading.

loaded.jpg (18031 bytes)

Balls loaded
into position.

shot1.jpg (18357 bytes)

Just after release.
(Simulated motion.)

end.jpg (15579 bytes)

End of track.

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