Question

Площадь каждой из пластин плоского конденсатора составляет 200 кв см,а расстояние между ними 1 см.Определите энергию поля , если напряжённость 500 кВ/м (Ответ должен получиться 200 мкДж)

Answer 1

W = CU^2/2

Напряжение:

U = E*d = 5*10^3 В

Найдем емкость конденсатора:

С = е0*S/d = 8,85*10^(-12)*0,02/0,01 = 17,7*10^(-12) Ф

Находим энергию поля:

W = 17,7*10^(-12)*25*10^(6) /2 = 200 мкДж (примерно)

Answer 2

Calculating the Energy of the Electric Field in a Capacitor

To calculate the energy of the electric field in a capacitor, we can use the formula:

U = (1/2) * ε * E^2 * A

Where: - U is the energy stored in the electric field - ε is the permittivity of the material between the plates - E is the electric field strength - A is the area of each plate

Given: - Area of each plate, A = 200 cm^2 = 0.0002 m^2 - Distance between the plates, d = 1 cm = 0.01 m - Electric field strength, E = 500 kV/m = 500000 V/m

First, we need to calculate the permittivity of the material between the plates using the formula:

ε = ε₀ * εᵣ

Where: - ε₀ is the vacuum permittivity (8.854 x 10^-12 F/m) - εᵣ is the relative permittivity of the material between the plates

Let's calculate the energy of the electric field using the given values.

Calculation

1. Calculate the permittivity of the material: - ε₀ = 8.854 x 10^-12 F/m - εᵣ can be assumed to be 1 for air

ε = 8.854 x 10^-12 F/m * 1 = 8.854 x 10^-12 F/m

2. Calculate the energy of the electric field: - U = (1/2) * ε * E^2 * A - U = (1/2) * 8.854 x 10^-12 F/m * (500000 V/m)^2 * 0.0002 m^2 - U ≈ 0.0002 J

Conclusion

The energy of the electric field in the capacitor is approximately 0.0002 joules (J). This value does not match the requested value of 200 µJ. It's possible that there may be a mistake in the given values or the intended calculation. If you have further details or corrections, please provide them for a more accurate calculation.