Which expression correctly gives the electric field in terms of voltage and distance?

• A. E = V d
• B. E = d / V
• C. E = V / d
• D. E = V^2 / d

Answer: (C)

Electric field is the rate at which electric potential changes with distance. If you have a potential difference V across a distance d, the average field strength is E ≈ V/d. Bigger voltage over the same gap means a stronger field; a larger gap with the same voltage means a weaker field. In general, E = -dV/dx, and for a uniform drop this reduces to the magnitude E = V/d (the negative sign indicating direction from high to low potential). The other forms don’t match the units or the relationship between voltage and distance, so the correct expression is V/d.