The experimentally obtained specific charge of the electron is 1.7 into 1011 c/kg. Cathode ray tube: an evacuated tube which allows the unobstructed movement of cathode rays from a cathode to an anode. Hence, the specific charge at the electron is determined if the values of E, B and V are known. two basic physical phenomena which play a significant role in the experiment. Although both the cathode and the anode contribute in the vacuum arc evolution, the role of the cathode is more crucial, since the processes developing at the cathode surface initiate the breakdown and maintain constant radiance from the cathode surface throughout the whole arc process, driving the arc in a stable manner. In this case the direction of magnetic field is perpendicular to the direction of the motion of the charged particle. Thomson, using a device similar to a cathode ray tube discovered the. At this condition charge particle incident at point O at the fluorescent screen, If both magnetic and electric field are applied and their magnitude and direction is adjusted so that the charged particles move without deviation. This causes atoms in the glass to be raised to a higher energy level, producing a fluorescent glow. They travel at high speed when voltage is applied to the electrodes and some bypass the anode to strike the glass. The blue glass seals and platinum connections indicate a production date of late 1800, so it is possibly an experimental tube from the time that the X-rays were invented. Cathode rays are invisible but their effect is to excite atoms in the glass opposite of the cathode, by the anode. In case of applying magnetic field only, the charge particle deviate and finally incident at 02 as shown in figure. This early odd English tube has a length of about 50 cm with a simple tiny rod anode and a heavy metal cathode. When the charge particle moves under the action of electric field strength (E) it moves towards the +ve plate and finally incident at point O, at fluorescent screen. When sufficient amount of potential (V) is applied between the two electrodes electrons emitted from the cathode accelerate with velocity ‘v’ then, It consists of discharge tube in which two electrodes anode (A) and cathode(C) are present P1 and P2 are two parallel electric plates to generate electric field strength (E). Thomson experiment to determine the specific charge of the electron. Electron was discovered by J J Thomson by Cathode ray discharge tube experiment.

The experimental setup shown in the figure shows the modern J.J. IN this situation the direction of motion of electron remains perpendicular to both electric and magnetic field. The rays emerge normally from the cathode and can be focused by using a concave cathode. The rays travel in straight lines as they produce sharp shadows of objects placed in their path. The specific charge of an electron can be determined when electron moves in both magnetic field and electric field which are mutually perpendicular to each other so that the net force on the electron is made zero. The cathode rays were seen to possess the following properties: 1.

Cathode ray experiment significance