Assertion: cathode's electron | /r/CapableOf | form beam
Facets:
value: due to the voltage difference
type: CAUSE
value: within the tube
type: LOCATION
Source sentences:
text: The released electrons form a beam within the tube due to the voltage difference applied across the two electrodes, and the direction of this beam is then altered either by a magnetic or electric field to trace over the inside surface of the phosphorescent screen (anode), covered by phosphorescent material (often transition metals or rare earths).