Answer:
Magnitude of its angular momentum = 0.0017 kgm²/s
Explanation:
Angular momentum, L = Iω
I is mass moment of inertia and ω is angular velocity.
Phonograph is in disc shape,
[tex]\texttt{I for disc =}\frac{MR^2}{2}[/tex]
Radius = 0.5 x 48 = 24 cm = 0.24 m
Angular velocity, ω = 3.2 rad/s
Mass, M = 18 g = 0.018 kg
Substituting
[tex]L=\frac{0.018\times 0.24^2}{2}\times 3.2 =0.0017kgm^2/s[/tex]
Magnitude of its angular momentum = 0.0017 kgm²/s