A wire of some length is bent in the form of a ring of diameter `2a` having self inductance `L`, then `L` will depend upon `a` as:

Explanation

To determine how the self-inductance \( L \) of a wire bent into a ring of diameter \( 2a \) depends on \( a \), we can follow these steps:

### Step 1: Understanding Self-Inductance
Self-inductance \( L \) is a measure of how much magnetic flux is generated for a given current in the wire. The magnetic flux \( \Phi \) through the loop can be expressed as:
\[ \Phi = N \cdot B \cdot A \]
where \( N \) is the number of turns, \( B \) is the magnetic field, and \( A \) is the area of the loop.
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