Answer
Real part = $0$
Imaginary part = $-5$
Work Step by Step
A complex number is written as $a+bi$, where $a$ is the real part and $b$ is the imaginary part as it is multiplied to the imaginary unit $i$.
Writing the complex number as $0-5i$, we find that $0$ represents the real part while $-5$ represents the imaginary part.