Moment of Inertia of a uniform rectangular coil

Click For Summary
SUMMARY

The discussion focuses on calculating the moment of inertia for a uniform rectangular coil with a mass of 270 g and dimensions of 1m x 5m, oriented perpendicular to a 4.00-T magnetic field. The coil carries a current of 2.90 A and rotates around a specified axis. Participants clarify that the moment of inertia can be determined using the formula for a rectangular lamina about the x-axis, emphasizing that only the mass distribution perpendicular to the axis of rotation is relevant for this calculation.

PREREQUISITES
  • Understanding of moment of inertia concepts
  • Familiarity with torque equations
  • Knowledge of magnetic fields and their effects on current-carrying coils
  • Basic principles of rotational motion
NEXT STEPS
  • Study the formula for moment of inertia of various shapes, particularly rectangular laminae
  • Explore the relationship between torque and angular acceleration in rotational dynamics
  • Investigate the effects of magnetic fields on current-carrying conductors
  • Learn about the geometric center and mass distribution in physical objects
USEFUL FOR

Physics students, educators, and anyone involved in mechanics or electromagnetism who seeks to understand the dynamics of current-carrying coils in magnetic fields.

dpeagler
Messages
32
Reaction score
0

Homework Statement



A uniform rectangular coil of total mass 270 g and dimensions 1m x 5m is oriented perpendicular to a uniform 4.00-T magnetic field (the figure ). A current of 2.90 A is suddenly started in the coil.

Homework Equations



angular acceleration = torgue / moment of inertia

The Attempt at a Solution



Here is the image...

It rotates around axis 2

YF-27-45.jpg


I can't figure out how to find the moment of inertia of this shape. I know the basic formula, of moment of inertia and how you find it, but can't figure out how to tell how the mass is distributed. I'm pretty sure the parts of the rectangle that are parallel to the axis of rotation can be excluded, because they will cancel each other out, but the bars on the side are confusing me.

Any help is greatly appreciated.
 
Physics news on Phys.org
I am assuming axis 2 is the horizontal axis.

So just use the formula for the moment of inertia about the x-axis for a rectangular lamina.

Also, it is uniform, the mass acts at the geometric center of the rectangle.
 

Similar threads

Replies
25
Views
2K
  • · Replies 5 ·
Replies
5
Views
4K
Replies
24
Views
4K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 1 ·
Replies
1
Views
4K
  • · Replies 2 ·
Replies
2
Views
1K
Replies
1
Views
1K
Replies
1
Views
2K