Recent content by Tony the Tutor14

I sincerely appreciate the effort you’ve put into help me, but your teaching method isn’t effective at this point. I would prefer if someone else could please help. Thank you for your time.

Zero, because the platform isn’t moving.

No, because the axle is the axis of rotation, so there is no torque from it.

If the system consists of the boy and the platform, then there are no external forces acting on it. Therefore, The problem states it is free to rotate about its vertical axis. I can only assume it is fixed about that axis.

Gravity?

Rethink which conclusion?

I would appreciate some more assistance. I am not a student. I’m trying to help my son with his exam prep.

Ok, so no law of conservation. Now I’m stuck on using KE to solve this problem.

I would choose the axis of the platform and I believe the boy creates a torque about that axis.

I don’t know. Right now, using the formulas for conservation of momentum and energy, I don’t see a path to calculate the correct answer. Any direction you can provide me would be very helpful. Out of the 15 questions in this problem set this is the only one I have not solved.

How about the conservation of angular momentum?

Sorry. This is my first post. I’ve tried a few different ways to solve it. Set KE of the boy = KE of the disk and solve for w. I calculated the mass of the disk for use in the KE equation. None of these have worked.

Homework Statement : [/B] A stationary horizontal platform is free to rotate about its vertical axis. The radius of the platform is R=1.6m and its moment of inertia is 660 kgm^2. A 43 kg boy jumps on the rim of the platform with the velocity 2.2 m/s tangential to the rim. What will be the...