8. A 4.70 m long pole is balanced vertically on its tip. What will be the speed (in meters/second) of the tip of the pole just before it hits the ground? (Assume the lower end of the pole does not slip.)

I did V^2=0^2+2(9.8)(4.70) and was wrong. I did remember to square root at the end. My answer was 9.60 m/s^2.

4 answers

m/s* sorry
yes, it is wrong. That would be the speed of the center of mass, but it is rotating, so the tip speed would be twice that.
I doubled 9.60 and it still said I was wrong.
The equation is mg(L/2)=1/2(1/3ML^2)w^2+1/2mw^2(L^2/4).
M's cancel out.
Take the answer and multiply by length.
That is the final answer.