Cathode Ray Tube
Accession Number: 2009.ph.212
A black turned wooden base with a 17cm glass tube mounted vertically onto the wooden base. There is a curved electrode plate on the bottom of the glass tube and another electrode on the top of the glass tube.
Alternative Name: Crookes tube; Vacuum Tube
Primary Materials: Metal, Wood, Glass
Markings: Old inventory number = phy65.
Dimensions (cm): Height = 25.5 cm, Diameter = 8.7 cm
Used to demonstrate the linearity of cathode rays through fluorescence.
Likely made by Richard Muler-Uri (Braunschweig).
Date of Manufacture:
If undisturbed by a magnetic field, cathode rays travel in straight lines. Due to the hemispherical curve of the cathode, the rays that emerge normal to the plane of their curve converge mid-beam, some distance away from the cathode.