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UkoKoshka [18]
3 years ago
12

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 loca

ted 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?
Physics
2 answers:
frutty [35]3 years ago
7 0

Answer:

L = 5.44 kg m^2/s

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

I = \frac{1}{2}mR^2

I = \frac{1}{2}(13 kg)(0.2)^2

I = 0.26 kg m^2

now in order to find the angular momentum we know that

L = I\omega

L = 0.26 \times \omega

here angular velocity is given by

\omega = \frac{2\pi}{T}

\omega = \frac{2\pi}{0.3}

\omega = 21 rad/s

now angular momentum is given as

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

kicyunya [14]3 years ago
6 0
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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(c) 5.82\cdot 10^6 J

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\Delta U = mg L sin \theta = (950)(9.8)(1250)(sin 30^{\circ})=5.82\cdot 10^6 J

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