As part of the optics in a prototype scanning electronmicroscope you have a unif

As part of the optics in a prototype scanning electronmicroscope you have a uniform circular ring of charge Q=4.80microCoulombs and radius R=1.30 cm located in the x-y planecentered on the origin as shown in the figure. If z is much smallerthan R then E is proportional to z. (You should verify this bytaking the limit of your expression for E for z much smaller thanR.) If you place an electron on the z-axis near the origin itexperiences a force Fz=-cz where c is a constant. Obtain anumerical value for c. (To think about: what kind of motion wouldthat electron undergo if you let it go?)