An Online O’Level Physics Book

http://home.att.net/~cat4a/index.htm

This is a good Physics teaching resource for O’Level.

The book written in the tradition fashion, covers topics like: Motion and Force, Newtons’ Laws of Motion, Gravitation,Archimedes’ Principle, Static and Current Electricity, Magnetism, Heat , Light ,………

http://scienceworld.wolfram.com/physics/CathodeRayTube.html
This is a good resource to explain how cathode ray tube works in mordern Physics for A’Level Science students.