Will a Meter Stick Rotate Around Its Center of Mass When Released?

In summary, the conversation discusses the motion of a meter stick being swung and released, and the question of where it will rotate before hitting the ground. The answer is at the 50cm mark, due to the force of gravity acting at the center of mass. The conversation then shifts to a new question about the travel times of three different paths for a mass projected with the same initial velocity. The answer choices for the relation among the travel times are t3<t2<t1, t2<t3<t1, t2<t1=t3, and t2=t3<t1. The ball in the straight track arrives faster due to the absence of friction.
  • #1
nothing123
97
0
Very quick question: A uniform meter stick held by one end is swung in an arc and released when the person’s arm is horizontal, so that it moves initially away from the ground. About which point will it rotate as it flies before striking the ground?

Is it the 50cm mark since once released, the only force acting is gravity which acts at the centre of mass?

Thanks.
 
Physics news on Phys.org
  • #2
Why would it rotate at all?
 
  • #3
Whoops, you're right.

I have another question: A mass m starting at point A is projected with the same initial
horizontal velocity v0 along each of the three tracks shown here
(with negligible friction) sufficient in each case to allow the mass
to reach the end of the track at point B. (Path 1 is directed up,
path 2 is directed horizontal, and path 3 is directed down.) The
masses remain in contact with the tracks throughout their
motions. The displacement A to B is the same in each case, and
the total path length of path 1 and 3 are equal. If t1, t2, and t3 are
the total travel times between A and B for paths 1, 2, and 3,
respectively, what is the relation among these times?

Picture attached.

Does the ball in the straight track arrive faster? Why is that?
 

Attachments

  • Snap1.bmp
    77.9 KB · Views: 574
  • #4
These are the answer choices to the above question;

a) t3<t2<t1
b) t2<t3<t1
c) t2<t1=t3
d) t2=t3<t1
 

Related to Will a Meter Stick Rotate Around Its Center of Mass When Released?

1. What is the axis of rotation in relation to the 50cm mark?

The axis of rotation is an imaginary line around which an object rotates or spins. In this case, the 50cm mark refers to the distance from the axis of rotation to a specific point on the object.

2. How is the 50cm mark determined as the axis of rotation?

The 50cm mark is typically determined as the axis of rotation by measuring the distance from the center of mass of the object to the point of rotation. This distance is often referred to as the moment arm or lever arm.

3. Can the axis of rotation change over time?

Yes, the axis of rotation can change over time. This can occur due to external forces acting on the object, causing its rotation to shift. Additionally, changes in the distribution of mass within the object can also alter the location of the axis of rotation.

4. How does the axis of rotation affect an object's motion?

The axis of rotation plays a crucial role in determining an object's motion. It determines the direction and speed of the object's rotation, as well as the amount of force needed to cause rotational motion. The closer the axis of rotation is to the object's center of mass, the easier it is to rotate.

5. Is the axis of rotation always located within an object?

No, the axis of rotation does not have to be located within an object. For example, a hula hoop rotates around an axis of rotation that is located outside the hoop itself. This is known as an external axis of rotation.

Similar threads

  • Introductory Physics Homework Help
Replies
5
Views
231
  • Introductory Physics Homework Help
Replies
18
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
1K
Replies
32
Views
1K
  • Introductory Physics Homework Help
Replies
13
Views
2K
  • Introductory Physics Homework Help
Replies
4
Views
1K
  • Introductory Physics Homework Help
Replies
14
Views
2K
  • Introductory Physics Homework Help
Replies
1
Views
468
  • Introductory Physics Homework Help
Replies
3
Views
2K
  • Introductory Physics Homework Help
Replies
3
Views
1K
Back
Top