A closed circuit consits of a source of constant and `E` and a choke coil of inductance `L` connected in series. The active resistance of the whole circuit is equal to `R`. At the moment `t = 0` the choke coil inductance was decreased abrupty `eta` times. FInd the current in the circuit as a function of time `t`.

Explanation

To find the current in the circuit as a function of time \( t \) after the inductance of the choke coil is abruptly decreased by \( n \) times, we can follow these steps:

### Step 1: Write the circuit equation
At \( t = 0 \), the circuit consists of a voltage source \( E \), a resistance \( R \), and an inductance \( L \). The equation for the circuit can be written using Kirchhoff's voltage law:
\[ E - Ri - \frac{L}{n} \frac{di}{dt} = 0 \]
where \( \frac{L}{n} \) is the new inductance after it is decreased by \( n \) times.
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