Question

энергия магнитного поля, запасенная в катушке индуктивности при силе тока 60 мА, составляет 72 мДж. Найти индуктивность катушки

Answer 1

Calculation of Inductance

To find the inductance of the coil, we can use the formula that relates the energy stored in the magnetic field of an inductor to its inductance and current:

Energy stored in the magnetic field (W) = (1/2) * L * I^2

Where: - W is the energy stored in the magnetic field - L is the inductance of the coil - I is the current flowing through the coil

Given that the energy stored in the magnetic field is 72 mJ (millijoules) and the current is 60 mA (milliamperes), we can substitute these values into the formula and solve for the inductance (L):

72 mJ = (1/2) * L * (60 mA)^2

Converting the current to amperes (A) by dividing by 1000, we have:

72 mJ = (1/2) * L * (0.06 A)^2

Simplifying the equation further:

72 mJ = (1/2) * L * 0.0036 A^2

To solve for L, we can rearrange the equation:

L = (72 mJ) / [(1/2) * 0.0036 A^2]

Calculating the value:

L = (72 * 10^-3 J) / [(1/2) * 0.0036 A^2]

L = (72 * 10^-3 J) / (0.0018 A^2)

L = 40 H (henries)

Therefore, the inductance of the coil is 40 henries.