A uniform disk has a moment of inertia that is (1/2)MR2. A uniform disk of mass 13 kg, thickness 0.3 m, and radius 0.2 m is located at the origin, oriented with its axis along the y axis. It rotates clockwise around its axis when viewed from above (that is, you stand at a point on the +y axis and look toward the origin at the disk). The disk makes one complete rotation every 0.3 s.
What is the rotational angular momentum of the disk?

The angular momentum of an object is equal to the product of its moment of inertia and angular velocity.
L = Iω
I = 1/2 MR²
I = 1/2 x 13 x (0.2)
I = 1.3

ω = 2π/t
ω = 2π/0.3
ω = 20.9

L = 1.3 x 20.9
= 27.2 kgm²/s

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aristocles aristocles · Answer 2 · 2019-04-16T02:58:33+02:00

Answer:

[tex]L = 5.44 kg m^2/s[/tex]

Explanation:

here we know that

mass of the disc is m = 13 kg

here we know that radius of disc = 0.2 m

now we have moment of inertia given as

[tex]I = \frac{1}{2}mR^2[/tex]

[tex]I = \frac{1}{2}(13 kg)(0.2)^2[/tex]

[tex]I = 0.26 kg m^2[/tex]

now in order to find the angular momentum we know that

[tex]L = I\omega[/tex]

[tex]L = 0.26 \times \omega[/tex]

here angular velocity is given by

[tex]\omega = \frac{2\pi}{T}[/tex]

[tex]\omega = \frac{2\pi}{0.3}[/tex]

[tex]\omega = 21 rad/s[/tex]

now angular momentum is given as

[tex]L = 0.26 \times 21 = 5.44 kg m^2/s[/tex]