Rotational Motion with a Suspended Hinge

Click For Summary
SUMMARY

The discussion centers on solving a physics problem involving a thin rod of mass 0.490 kg and length 1.16 m, suspended from a fixed hinge. An impulsive horizontal force of 12.7 N is applied at different points on the rod to analyze the resulting acceleration of the center of mass and hinge forces. Key equations include Fnet=ma and the torque equation, torque = moment of inertia times angular acceleration. The concept of the center of percussion is also introduced, indicating the point where the hinge exerts no horizontal force.

PREREQUISITES
  • Understanding of Newton's Second Law (Fnet=ma)
  • Knowledge of torque and moment of inertia
  • Familiarity with the concept of center of mass
  • Basic principles of rotational motion
NEXT STEPS
  • Study the application of torque in rotational dynamics
  • Learn about calculating moment of inertia for different shapes
  • Explore the concept of center of percussion in physics
  • Investigate the effects of impulsive forces on rigid bodies
USEFUL FOR

Students studying physics, particularly those focusing on mechanics and rotational motion, as well as educators seeking to enhance their understanding of dynamics involving rigid bodies.

MF92
Messages
2
Reaction score
0
The Problem:
A thin rod of mass 0.490 kg and length 1.16 m is at rest, hanging vertically from a strong, fixed hinge at its top end. Suddenly, a horizontal impulsive force (12.7) N is applied to it.
a) Suppose the force acts at the bottom end of the rod. Find the acceleration of its center of mass.
(b) Find the horizontal force the hinge exerts.
(c) Suppose the force acts at the midpoint of the rod. Find the acceleration of this point.
(d) Find the horizontal hinge reaction force.
(e) Where can the impulse be applied so that the hinge will exert no horizontal force? This point is called the center of percussion.

2. Homework Equations
Fnet=ma
Fnet=m(accelertaiton of center of mass)

3. The Attempt at a Solution
I attempted to use the Fnet equation to solve for the acceleration but I got the wrong answer. I'm nor sure how to fiqure out the parts b or d and I'm sure that once I fiqure our part a part c wil be fairly easy. I'm kinda running around in circles with this problem. If someone could just give me a jumping off point, not necessarily the answer, i would greatly appreciate it. Thanks!
 
Physics news on Phys.org
Use the relation torque = moment of inertia times angular acceleration, too.

ehild
 
Last edited:
Thank you very much , that helped a lot! It was that push in the right direction that I needed.
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
4K
Replies
2
Views
3K
  • · Replies 11 ·
Replies
11
Views
4K
Replies
5
Views
2K
  • · Replies 17 ·
Replies
17
Views
2K
Replies
1
Views
2K
  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 11 ·
Replies
11
Views
4K
  • · Replies 65 ·
3
Replies
65
Views
13K
Replies
11
Views
4K