Answer:
w = wâ‚€ / 2 Â Â the angular velocity is half the initial value.
Explanation:
We can analyze this exercise as if we added another disk to obtain a disk with twice the mass, for which if the system is two disks, the angular tidal wave is conserved
initial instant.
     L₀ = I₀ w₀
final moment
     L_f = I w
the moment is preserved
     L₀ = L_f
     I₀ w₀ = I w
the moment of inertia of a disk is
     I = ½ m R²
we substitute
     ½ m R² w₀ = ½ (2m) R² w
     w = w₀ / 2
for the case of a disk with twice the mass, the angular velocity is half the initial value.