Merry Go Round Effect - Understand its Physics & Answer Daughter

[donbcg]

Gentlemen,

Your humble science intelect required.

My daughter and I were riding a merry go round recently and as we were spinning she realized that if she pushed her upper body to the center and back out agian the rpm increased and we spun faster.

I am a PLC/PC programmer and haven't the best way to answer her. I was ashamed simply and would appreciate the correct answer.

Thank you.

 

[CS Bence]

I can only explain it when she moves her body to the center that it will increase, but when she moves her body back to where she started you should be going the same speed. This is due to the conservation of angular momentum, like when a figure skater is spinning like a top and they open their arms they slow down due to more mass being further away from the center.

But moving her body directly from the inside to the out shouldn't actually change your RPM... Unless you push against the ground or something else, you're not adding any energy into the system.

But I could be missing something! :)