Mavir (Lighting a Fire) - Breaking Down the 39 Melachot

Are you allowed to put lights outside your  home that are motion-sensitive so that if   someone passes in front of your house or walks  towards the back that the light will turn on?   One of the melachot of Shabbat is the melacha of  Mavir, which means lighting a fire. Many light   bulbs have the status of fire in the Torah, and  therefore you should not put up a motion-sensitive   light outside your home because that will mean  that the people passing by your home will turn   on the lights and create a fire. Similarly,  if a person has nanny cams or other security   cameras or motion sensors in their home, you  should make sure that if they're on on Shabbos,   that they don't create a light, that a light  does not go on when they sense somebody going by.