I don't know if they would be able to produce the same type of strength they had in their physical body.  I suppose the intensity of emotions and certain conditions could inhabit or magnify a spirit's kinetic energy. 
 Just as an example, a few months ago I had a large medicine cabinet in my bathroom seemingly hurled off the wall.  We never could find a reasonable explanation for it.  I don't believe my house is haunted, but I do feel that I get the occasional "visitor" that just passes through.  Whatever hurled that cabinet off had to have a great deal of strength and I suppose with that, some pretty strong emotions and/or need to get my attention.  My theory on the incident is that whatever was "visiting" at the time was able to gain strength from a simultaneous thunderstorm we had during the incident.
I also believe the personality a spirit had while in their physical body may have a lot to do with how much they are able to manipulate physical objects.  A person who was shy and retiring in life, likely would not be throwing ojbects around or hiding things in spirit form.  One who was mischieveous or hot tempered probably would.  I think the personality traits a person has in life carries over after life on the physical plane has ended.
Interesting question, certainly something to ponder!