# Am I right ?

• posted

Hi

An object is attached near the periphery of a bigger one and the bigger object is rolling. After some time the link between the two breaks and the smaller one flies off tangentially.

I want to know whether in addition to its tangential translation will the smaller object spin too ?

I think it should spin as it should inherit rotational motion which it experienced while being on-board the larger object. And that spin rate should be equal to the rate of roll of the larger object. The mass center of the smaller obj however moves along the straight line tangentially.

Am i right ?

Thanks and regards

RJ Khan

• posted

Yes, almost all of the time. The key word is breaks which implies force. It is possible the force that breaks the two objects apart also stops the rotation of the small object. This would be a rare accidental fluke. If this needs to happen all the time one would need to calculate the force to cause the two object to break apart and the point on the small object to apply the force so that the small object wouldn't spin. If you had used the words separated without external force, then you are right 100% of the time. There would be no force/ torque to stop the rotation.

Peter Nachtwey

• posted

Thanks a lot Actually, some one wants a reference for my point. I have looked into various resources books, internet etc but none talked about the spin. I will be grateful if anybody could refer me something addressing the exact detail of the problem.

Regards

RJ

• posted

Is Newton's first law of motion good enough?.

Peter Nachtwey

• posted

I have hinted to 1st law of newton already in my statement. The problem is the detailed kinemetical descriptive example which lacks my statement. The person i am trying to say is of the view that the smaller body should plainly translate. He might be satisfied if provided by some published matter corroborating my point.

RJ Khan

• posted

...

I find little satisfaction in convincing a fool to accept my opinion. If he doesn't believe in the conservation of angular momentum, what more is there to demonstrate?

Jerry

• posted

=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF= =AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF

Right!

Atleast THIS conerstation will do

By the way plz dont mind me insisting

Best regards

• posted

=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF= =AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF

The little object will have energy stored in it in the form of kinetic energy (one half times mass times translational velocity squared) because it is moving relative to the surface it is on. It will also have energy in the form of rotational energy (one half times mass moment of inertial times rotational speed squared - rotational speed is measured in radians per second), and it may also have energy in the form of potential energy (equal to mass times height times gravitational constant).

There is also heat energy and chemical energy stored in the little object but it won't matter here. You can find all of this in a Dynamics text or a Physics text. This would fall into the category of conservation of energy. It's probably in the section which explains impact.

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.