In the figure, a proton, mass 1.67 \times {{10}}^{{ -27}}{\rm \;kg}, is projected horizontally midway between two parallel plates that are separated...

In the figure, a proton, mass 1.67 times {{10}}^{{ -27}}{rm ;kg}, is projected horizontally midway between two parallel plates that are separated by 0.90{rm ;cm}, with an electrical field with magnitude 9.7×10^{5}{rm ;N/C} between the plates. If the plates are 4.30{rm ;cm} long, find the minimum speed of the proton that just misses the lower plate as it emerges from the field.