The electric field strength E₀ is measured at a perpendicular distance R from an infinitely large, thin sheet that contains a un
iform positive charge density σ. In terms of the stated properties and the permittivity of free space ε₀, write an expression for the electric field strength E at a perpendicular distance 2 R from the sheet?
As noted by Dirac the field is the same no matter how far you are from the sheet. When your charge covers a conducting plane, as in your case, the field is, D/eo ,(D is charge density). Because the field inside the conductor (no matter how thin) is zero. The only time the field is, D/2eo, is when you have just a sheet of charge, by itself, not on a conducting plane."
Assuming that reaching a height 0 doesn’t stop the ball, and that it accelerates at 9.8 m/s^2, the ball would be traveling at 0.5 + 0.7*9.8 = 7.36 m/s downwards.
