Question

Two parallel plates are placed at a distance of 1.0 cm at 10³ V potential difference. The electric field at the point between the two plates will be -
1. 10⁵ V/m
2. 10⁶ V/m
3. 10⁴ V/m
4. 10³ V/m

Answer 1

Correct Answer - Option 1 : 10⁵ V/m

Concept:

Electric Field: Electric Force per unit positive charge at a given point gives field at that point.

Electric Potential: The amount of work done required to be done per unit charge to bring a positive charge from infinity to that point is called Electric Potential.

The relationship between Field and Potential: The relationship between field and potential is given as

\(\frac{dV}{dr} = -E\)

dV = - E.dr

For average estimation we can say that

\(E = \frac{Δ V}{Δ r}\)

ΔV is potential difference, Δr is distance. 

The field is directed toward decreasing Potential.
Calculation:

So, here we have

ΔV = 103 V

Δr = 1 cm = 10 ^-2 m

Field

\(E = \frac{Δ V}{Δ r}\)

\(\implies E = \frac{10^3}{10^{-2}} V/m = 10^{(3 +2)} V/m\)

⇒ E = 10 ⁵ V / m

So, the correct option is 10 5 V / m