7—6.
ENERGY LEVELS ‘
149
atoms somewhere near the grid and give up all their energy.
This is true even though their energies are less than the minimum
ionizing potential. If the electrons had retained an energy greater
than 0.5 volt, they Would have been able to reach the plate and
the current would not have decreased as from  to B. As the
potential of the grid is still further increased, the electrons Will
acquire sufcient energy to cause au inelastic collision in front of
the grid and then acquire an additional velocity in the remainder - '
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of the potential gradient to the grid.- Thus, they are able to pass
to the plate against the 0.5 volt retarding potential; whereupon,
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ENERGY LEVELS ‘
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atoms somewhere near the grid and give up all their energy.
This is true even though their energies are less than the minimum
ionizing potential. If the electrons had retained an energy greater
than 0.5 volt, they Would have been able to reach the plate and
the current would not have decreased as from  to B. As the
potential of the grid is still further increased, the electrons Will
acquire sufcient energy to cause au inelastic collision in front of
the grid and then acquire an additional velocity in the remainder - '
'
of the potential gradient to the grid.- Thus, they are able to pass
to the plate against the 0.5 volt retarding potential; whereupon,
.,
35
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3°
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