Hi,
Without knowing if your application motor and object movement is horizontal, vertical, globular, opaque or transparent surface, in a clean or dirty environment, indoors or outdoors, aesthetically sophisticated or a learning tool for children... Lots of variables for better choice of switch.
Some switch (position sensing device options):
Non-contact magnetic - Reed relay (uses "a lot" of current for my tastes)
Hall Effect sensor (e.g. 3mA supply current)
"Non-contact" optical - light dependent resistor, LDR, easy to use, low suppy current (affected by ambient light conditions)
IR sensor and photodiode pair (bad for having to place one on the moving object and power it, low signal level needs shifting up)
Physical/contact sensing - limit switch (low power, easy to implement, could suffer from contact bounce which is simple to overcome, object may not force lever enough to actuate it or trajectory miss it competely but unlikely, might make project look clunky but avoidable).
There are other kinds, such as pressure sensors and so on.
Model railway designers are pretty cool precision application circuit designers who deal a lot with sensing moving objects, timing, stopping at the right place, etc. and their ideas and solutions might be a great help.