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Angular Momentum Question???
Figure 1145 (attached) shows a rigid structure consisting of a circular hoop of radius R and mass m, and a square made of four thin bars, each of length R and mass m. The rigid structure rotates at a constant speed about a vertical axis, with a period of rotation of 2.5s. Assuming R=0.50m and m=
2.0kg, calculate (a) the structure's rotational inertia about the axis of rotation and (b) its angular momentum about that axis.
I=[tex]\int[/tex]r^{2}dm
L=I_{[tex]\omega[/tex]}
(a) I did mr^{2} = (10)(.5)^{2 }= 2.5 (the answer is supposed to be 1.6
Then I tried m_{s}r_{s}^{2} + m_{c}r_{c}^{2} = (8)(.25)^{2} + (2)(.5)^{2 }= 1.5 (still incorrect)
(b) Due to not being able to solve "a" I could not began my attempt on "b"
Homework Statement
Figure 1145 (attached) shows a rigid structure consisting of a circular hoop of radius R and mass m, and a square made of four thin bars, each of length R and mass m. The rigid structure rotates at a constant speed about a vertical axis, with a period of rotation of 2.5s. Assuming R=0.50m and m=
2.0kg, calculate (a) the structure's rotational inertia about the axis of rotation and (b) its angular momentum about that axis.
Homework Equations
I=[tex]\int[/tex]r^{2}dm
L=I_{[tex]\omega[/tex]}
The Attempt at a Solution
(a) I did mr^{2} = (10)(.5)^{2 }= 2.5 (the answer is supposed to be 1.6
Then I tried m_{s}r_{s}^{2} + m_{c}r_{c}^{2} = (8)(.25)^{2} + (2)(.5)^{2 }= 1.5 (still incorrect)
(b) Due to not being able to solve "a" I could not began my attempt on "b"
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