In Thomson's method of determining e/m of cathode rays, magnetic field (B) and electric field ( E) are parallel a parabola is not. Obtained on the screen. The reason is _______ .

In Thomson's method of determining e/m of cathode rays, magnetic field

1.	In Thomson's method of determining e/m of cathode rays, magnetic field (B) and electric field ( E) are parallel a parabola is not. Obtained on the screen. The reason is _______ .
Answer» CATHODE rays consist of electrons which carry negative charge Electron is very light particle There is no velocity distribution in cathode rays Parallel fields B and E do not interact with electrons Solution :In case of POSITIVE rays we get a parabola when B and E are parallel because different positive ions have different VELOCITIES and they REACH at different points on the parabola. If the velocities of all the ions be the same, only a POINT will be obtained on the screen. Since there is no velocity - distribution in cathode rays , hence no parabola is obtained.

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In Thomson's method of determining e/m of cathode rays, magnetic field (B) and electric field ( E) are parallel a parabola is not. Obtained on the screen. The reason is _______ .

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