Step 1: Find the point where the particle hits the reflecting line.
The particle moves along
\[
x-2y-3=0
\]
It hits the line
\[
3x-2y-5=0
\]
Solving both equations,
\[
x-2y-3=0
\]
and
\[
3x-2y-5=0
\]
Subtracting the first equation from the second,
\[
2x-2=0
\]
So,
\[
x=1
\]
Substituting \(x=1\) in
\[
x-2y-3=0,
\]
we get
\[
1-2y-3=0
\]
\[
-2y-2=0
\]
Hence,
\[
y=-1
\]
Therefore, the point of reflection is
\[
(1,-1)
\]
Step 2: Find the slope of the original path.
The original path is
\[
x-2y-3=0
\]
Writing in slope form,
\[
2y=x-3
\]
\[
y=\frac{x}{2}-\frac{3}{2}
\]
So, its slope is
\[
m_1=\frac{1}{2}
\]
Step 3: Find the slope of the reflected path.
The reflected direction is perpendicular to the original direction.
Hence,
\[
m_1m_2=-1
\]
So,
\[
\frac{1}{2}m_2=-1
\]
Therefore,
\[
m_2=-2
\]
Step 4: Form the equation of the reflected line.
The reflected line passes through
\[
(1,-1)
\]
and has slope
\[
-2
\]
Using point-slope form,
\[
y-y_1=m(x-x_1)
\]
\[
y+1=-2(x-1)
\]
\[
y+1=-2x+2
\]
\[
2x+y-1=0
\]
Step 5: Final conclusion.
Hence, the line of movement after reflection is
\[
\boxed{2x+y-1=0}
\]