On Thursday, May 21, 2015 at 7:54:35 AM UTC-4, Frank wrote:
A force like magnetism decreases as the square of the distance.
In three dimensional space its usually the cube of the distance.

In the "near field," probably just the distance, not the cube.

We were working on the lawnmower last weekend and dropped one of the bolts in the grass, couldn't find it.

I got my biggest magnet and swept the area, no luck.

So I took one of the bolts I hadn't lost (yet) and threw it down to a known spot, so I could test the magnet. Reached down with the magnet and heard two clicks, sure enough both bolts were stuck to it. FAR better to be lucky than good.