Answer
The magnitude of the angular momentum of the middle particle is $~~1.1\times 10^{-3}~kg~m^2/s$
Work Step by Step
We can find the magnitude of the angular momentum of the middle particle:
$L = I\omega$
$L = mr^2~\omega$
$L = (0.023~kg)(0.24~m)^2~(0.85~rad/s)$
$L = 1.1\times 10^{-3}~kg~m^2/s$
The magnitude of the angular momentum of the middle particle is $~~1.1\times 10^{-3}~kg~m^2/s$
