a basic mass spectrometer can be constructed by shooting a charged particle through a pair of charged plates and measuring the deflection angle at the end of the plates. this device can measure the ratio of the charge to the mass of the particle. such a device is shown in the figure, which has a length l, a plate separation h, and a constant electric field e between the plates as shown. in this problem, you may assume the particle deflection is small relative to the separation h of the plates.