The central carbon in a free radical is `sp^3` hybridised.

Explanation

To determine the hybridization of the central carbon in a free radical, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Free Radicals**:
A free radical is a species that has an unpaired electron. In organic chemistry, free radicals are often represented as having a central carbon atom bonded to other atoms (like hydrogen) and possessing one unpaired electron.

2. **Counting Valence Electrons**:
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