# Homework Problem! (asap)

1. ### Heidikins07

3
Here is the homework question...

According to the Guinness Book of World Records, the highest rotary speed ever attained was 2010m/s(4500mph). The rotating rod was 15.3cm(6in.) long. Assume the speed quoted is that of the end of the rod. What is the centripetal acceleration of the end of the rod?

So I think since they say rotary speed they are talking about angular velocity here. so i would say angular velocity (w) = 2010m/s. Is this correct? or is it tangential velocity (v) = 2010m/s?

okay....does this mean it's rotating about the middle or about the end? (diameter being 15.3 radius being 7.65) orrrrrr (radius being 15.3 and diameter being 30.6) ??

Last edited: Apr 29, 2007
2. ### neutrino

What is the SI unit of angular speed?

Well, nothing has been stated specifically. If this written homework, you could check with your teacher. If this is one of those computerised tests, which gives you three chances at the right answer, then use 15.3 cm as the radius in your first try.

3. ### Heidikins07

3
yea, it's written homework. so i did it both ways and im just gunna ask my teacher! thanks tho! Ü