The mass of an atom is constituted mainly by

Write down the results of the cathode ray discharge tube experiment.

$A$ particle having the same charge and $200$ times greater mass than that of an electron is:

Fill in the blanks given below:
$(i)$ The picture on the television screen is visible due to the presence of .......... on the screen.
$(ii)$ In the presence of electric and magnetic fields,cathode rays are known as .......... .
$(iii)$ The measurement of the $e/m_e$ ratio for electrons was performed by the scientist .......... .
$(iv)$ In a cathode ray tube,the greater the magnitude of the charge on the particles,the .......... the deflection of the particles.

Which of the following pairs has the identical $e/m$ value?

Which of the following statements regarding cathode rays is incorrect?