I have a board 4 ft. long with two 3 lb. weights on the ends?

Question

and an axle in the center. How fast must this board rotate about the axle to experience enough g's to where the weights would seem like they weighed 12 lbs?

just looking for a site or place to find the calculation or info, not for someone to do my homework

Answer 1

Than means you want to subject the 3lb weights  to a 4g acceleration so they would seem to weigh 12lb.

Centripetal acceleration is (ref 1)

a= 4g= V^2/R = w^2 R

w= sqrt( 4g/R)

w= 2sqrt( g/R)