- A particle possessing q = 3.25 C of charge and a mass of m = 7.55 g is fired at a speed of v = 357 cm/s between two horizontal charged plates of length L = 64.9 cm. Assume that the electric field between the plates is uniform and has a constant value of E = 4560 N/C, directed upwards. Calculate the distance y by which the charge falls below a straight-line path when it reaches the end of the plates. Assume a gravitational acceleration of g = 9.81m/s. y= + + + +++++ cm