Physics II Lab w answers_Part_21

Physics II Lab w answers_Part_21 - calculation of the e/m...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
53 Calculations: Results: Calculated value of specific charge of electron (e/m) = __________________ C/Kg. Standard Value of (e/m) = _________________ C/Kg % error in e/m = _________________. Displacement O E 2 2 o m sin B T T B = [ ] 2 2 o 2 m d L d d B I - + = 2 I s y V a L 2 a m e ± ² ³ ´ µ + = 1 2 3
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
54 Experiment 9 Measurement of “(e/m)” by helical coil method Apparatus: Cathode ray tube (CRT), CRT power supply, DC power supply (30V), solenoid, Rheostat, DC voltmeter, and connecting wires. Purpose of experiment: To measure the specific charge, i.e. .charge to mass ratio (e/m) of an electron. Basic methodology: Electrons are accelerated towards the screen of a CRT and also deflected by a transverse AC voltage. The CRT is placed in a magnetic field produced by a solenoid. The resulting motion of the electron is then helical .A measure of the pitch of the helix leads to a
Background image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: calculation of the e/m ratio . ________________________________________________________________________ Introduction 1.1 Electron are emitted at the cathode of a CRT and accelerated through an accelerating DC voltage V a towards the screen. In addition a small transverse (AC) voltage acts across the XX / plates. . Once the electron leaves the plate region its velocity v is constant and makes angle & with Z-axis. The component of its velocity along Z-axis is v || =v cos & & When the AC deflecting velocity is switched on, different electrons receive varying velocity v and hence a line gets formed on the CRT screen. fig 1 I.2 When the CRT is placed along the axis of the solenoid then there is a magnetic field B= o n I (along the axis of the solenoid) which acts on the electron. Here n=number of turns per unit length of the solenoid and I=current in the solenoid, length of the solenoid and I=current in the solenoid....
View Full Document

This note was uploaded on 11/26/2011 for the course PHY 2053 taught by Professor Lind during the Fall '09 term at FSU.

Page1 / 2

Physics II Lab w answers_Part_21 - calculation of the e/m...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online