This problem deals with several aspects of an oscilloscope. You have an15500volt supply (Vsupply) for accelerating electrons to a speed adequate to make the front phosphor-coated screen glow when the electrons hit it. Once the electron has emerged from the accelerating region, it coasts through a vacuum at nearly constant speed. You can apply a potential difference of plus or minus32volts (Vplates) across the deflection plates to steer the electron beam up or down on the screen to paint a display (other deflection plates not shown in the diagram are used to steer the beam horizontally). Each of the two deflection plates is a thin metal plate of lengthL=8 cm and width (into the diagram) 4 cm. The distance between the deflection plates iss=7mm. The distance from the deflection plates to the screen isd=25cm.

Accelerating V plates Deflection plates (Exaggerated Hot + or - volts vertical filament scale) L . - (not to scale ) Phosphor-coated screen glows when hit by electrons