Electrons are observed to be ejected in various directions with negligible speed from the negative plate of a parallel plate capacitor when the plate is illuminated by a certain wavelength. The plates are separated by a distance d and a potential difference V is maintained between them. Show that none of these electrons will reach the positive plate if a magnetic field is applied at right angles to the electric field and that the magnetic induction has a value B gt ((2m V)/(ed^(2)))^(1/2) where m and e are the electron mass and charge respectively.

Electrons are observed to be ejected in various directions with neglig

1.	Electrons are observed to be ejected in various directions with negligible speed from the negative plate of a parallel plate capacitor when the plate is illuminated by a certain wavelength. The plates are separated by a distance d and a potential difference V is maintained between them. Show that none of these electrons will reach the positive plate if a magnetic field is applied at right angles to the electric field and that the magnetic induction has a value B gt ((2m V)/(ed^(2)))^(1/2) where m and e are the electron mass and charge respectively.
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