E/M Helical Method Appratus
E/M Helical Method Appratus
In the helical method a cathode-ray tube is inserted in a solenoid and e/m determined from the condition for focusing deflected electrons to a spot on the screen.
OBJECT: To determine the value of e/m for an electron by Helical method.
APPARATUS: The set of Experimental set up comprises of the following:
1. DC Power supply for apparatus comprises of the following built in parts:
(a) H.T. (High Tension) DC power supply continuously variable from 375V to 850Vą5% for acceleration voltage control.
(b) DC Power supply for solenoid 0-60VDC variable in steps through two band switches (5 steps) using fine and coarse controls
band switches.
(c) Potentiometers are mounted on the front panel for Focus control, Intensity control and X, Y shift controls.
(d) Two meters to measure acceleration voltage &solenoid current are mounted on the front panel.
(e) Eight pin octal bases are mounted on the front panel to connect the CRT plug.
2. One long solenoid wound on 4 dia PVC with 23 wire gauge, mounted on wooden stand & connections brought out at terminals.
3. CRT mounted inside the solenoid.
Input : 230 volts AC 50c/s
E.H.T. : 1000 volts
DC Output for
Solenoid Provided : 60 volts DC at 1.5 Amps
Solenoid : Dia 4"-5"
Length : 20" wound on properly insulated former and fitted on nicely Polished teak wood base.
