Final answer:
To find the value of Δvba, one can use the formula for electric field strength E = ΔVba / d, resulting in 5.00 × 105 V/m given the provided potential difference and distance.
Step-by-step explanation:
The value of Δvba = vb - va in an electric field can be determined using the equation E = ΔVba / d, where E is the electric field strength, ΔVba is the potential difference between points a and b, and d is the distance between these points. Given that the problem states the potential difference needed for the electron to gain 25.0 keV (or 25.0 kV) of energy, and that the distance between the plates is 5.00 cm, we convert that to meters to get 0.05 meters. Using the equation, the electric field E can be calculated as 25.0 kV / 0.05 m, resulting in an electric field strength of 5.00 × 105 V/m.