Re: [Phys-l] Photocopier toner

[Bernard Cleyet <bernardcleyet@redshift.com>]

This is obvious from experience.   The strongest person can not pull  
a door open from a magnetic lock yet easily hold it a jar when an  
inch or two away.

bc  wonders why not seen or read of the experiment using a force  
gauge (or calibrated spring) and two small PMs.

bc  suspects the door would be severely damaged or the handle removed  
if one used the winch on a land rover.


On 2009, Mar 27, , at 15:33, John Denker wrote:

> As a specific sub-case, is useful and interesting to work out
> the force on an induced dipole in the field of a strong permanent
> dipole.  The result is a power law, with an impressively large
> exponent.