Help me understand a misconception....

[asterroc]

An interesting situation came up in my Physics class today, where two of my students surprised me with a question they asked. To try and understand their thinking so I can teach the content better, I'd like to ask that everyone take a look at the below situation and tell me what you think will happen. I don't care if you know any physics or if you're a professional ear-wax taster, I want to know what you think and why.

In the picture below, Box 1 (m₁) is hanging from a string that passes over a pulley. There's no friction in the pulley, and the pulley has no mass, so it can spin freely. The string is then connected to Box 2 (m₂) sitting on a table. For simplicity, let's assume there's no friction on the table - there's some lubrication between the box and the table.



[Poll #1162218]

X-posted a couple places.

Comments

[zandperl.livejournal.com]

Well, so long as we assume μ<1 - although we learn that in intro physics, in reality some materials have μ>1, such as rubber, or under special circumstances, such as two smooth sheets of aluminum which are perfectly clean or two smooth sheets of glass with a film of water between them.

[spoonless.livejournal.com]

Oh, you're right! For some reason, I never knew you could have mu > 1... I'm glad I stumbled onto this poll :)

For boxes, it would seem somewhat unrealistic to have a mu that large. But I guess the whole question was not intended to be realistic.