Answer:
The radius of the circular plate is 0.774 m
Explanation:
Given;
distance between the parallel plates, d = 1.53 cm = 0.0153 m
electric field energy density between plates, [tex]U_E[/tex] = 4.41 J/m³
Potential energy of the capacitor, [tex]U_c[/tex] = 0.127 J
Energy density is given as;
[tex]U_E = \frac{U_c}{V}[/tex]
where;
V is volume
[tex]V = \frac{U_c}{U_E} = \frac{0.127}{4.41} = 0.0288 \ m^3[/tex]
Volume is given as;
V = Ad
where;
A is area
A = V / d
A = (0.0288) / (0.0153)
A = 1.882 m²
Area of circular plate is given as;
A = πr²
where;
r is the radius of the circular plate
[tex]r = \sqrt{\frac{A}{\pi} } \\\\r = \sqrt{\frac{1.882}{\pi}}\\\\r = 0.774 \ m[/tex]
Therefore, the radius of the circular plate is 0.774 m
