Question

Two flat 4.0 cm 4.0 cm electrodes carrying equal but opposite charges are spaced 2.0 mm apart with their midpoints opposite each other. Between the electrodes but not near their edges, the electric field strength is 5.5 106 N/C. What is the magnitude of the charge on each electrode? (? 0 = 8.85 10-12 C2/N m2)

Answer 1

Answer:

The magnitude of the charge on each electrode is 77.8 nC.

Explanation:

Given that,

Length = 4.0 cm

Distance = 2.0 mm

Electric field strength $E=5.5\times10^{6}\ N/C$

We need to calculate the magnitude of the charge on each electrode

Using formula of electric field

$E=\dfrac{\sigma}{\epsilon_{0}}$

Where, $\sigma$ = charge density

We know that,

The charge density is

$\sigma=\dfrac{Q}{A}$

Put the value of charge density into the formula of electric field

$E=\dfrac{Q}{A\epsilon_{0}}$

$Q=EA\epsilon_{0}$

Put the value into the formula

$Q=5.5\times10^{6}\times4.0\times4.0\times10^{-4}\times8.85\times10^{-12}$

$Q=77.8\times10^{-9}\ C$

$Q=77.8\ nC$

Hence, The magnitude of the charge on each electrode is 77.8 nC.