When the current strength in the inductor changes by ΔI = 1 A during the time Δt = 0.6 s, an EMF

When the current strength in the inductor changes by ΔI = 1 A during the time Δt = 0.6 s, an EMF is induced in it, equal to e = 0.2 mV. What is the length of the radio wave emitted by the generator, the oscillating circuit of which consists of this coil and a capacitor with a capacity of C = 14.1 nF?

The process of changing the current in the coil is described by the formula:

έ = -L * ΔI / Δt, L – inductance, ΔI – change in current strength, Δt – time. The minus sign indicates the direction of the current strength, in this case it does not matter.

L = έ * Δt / ΔI = 0.2 * 10 ^ (- 3) * 0.6 / 1 = 0.12 mH.

The natural cyclic frequency of the oscillatory circuit is determined by the formula:

ω = 1 / √LC = 1 / √14.1 * 10 ^ (- 9) * 0.12 * 10 ^ (- 3) = 0.77 * 10 ^ (6).

Then the frequency will be:

f = ω / 2π = 0.122 * 10 ^ (6).

l = f / c = 0.122 * 10 ^ (6) / 3 * 10 ^ 8 = 4 * 10 ^ (- 4) m.