In the below figure, an electron of mass m, charge-e, and low(negligible) speed enters the region between two plates of potential difference V and plate separation d, initially headed directly toward the top plate. A uniform magnetic field of magnitude B is normal to the plane of the figure. Find the minimum value of B such that the electron will not strike the top plate.

In the below figure, an electron of mass m, charge-e, and low(negligib

1.	In the below figure, an electron of mass m, charge-e, and low(negligible) speed enters the region between two plates of potential difference V and plate separation d, initially headed directly toward the top plate. A uniform magnetic field of magnitude B is normal to the plane of the figure. Find the minimum value of B such that the electron will not strike the top plate.
Answer» `sqrt((2mV)/(ed^(2))` `sqrt((mV)/(2ed^(2))` `sqrt((mV)/(ed^(2))` `2sqrt((mV)/(ed^(2))` ANSWER :B

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