The expression \( 5-\sqrt{3} \) can be rewritten in terms of rational exponents.
The square root of a number can be expressed as a rational exponent. Specifically, for any positive number \( a \), the square root can be represented as \( a^{1/2} \).
Thus, \( \sqrt{3} \) can be expressed as \( 3^{1/2} \).
Now, we can substitute this into the expression:
\[ 5 - \sqrt{3} = 5 - 3^{1/2} \]
In this case, the rational exponent corresponding to \( \sqrt{3} \) in fractional form is \( \frac{1}{2} \).
Therefore, the answer is:
\[ \frac{1}{2} \]