Is throwing a ball upwards an isolated or non-isolated system? We have to write a lab report on an experiment where a ball is thrown upwards and it's motion is detected by a motion sensor, i am just confused whether the system is isolated or non-isolated 
 A: Normally, an isolated system means that no energy, momentum or angular momentum enters of leaves the system. These quantities are conserved for the system. The best way to answer the question of whether isolated or not is to imagine a boundary around the system and ask: does any energy, momentum or angular momentum pass through it? OR: are there only interactions between members of the system alone, or do some parts of the system interact with things outside the system?
By this thinking, a ball in flight is clearly not isolated: the Earth is imparting a constant force on it (in the Newtonian framework) from outside the system, so its momentum is changing. When the system comprises both ball and Earth, momentum, energy and angular momentum conservation is restored. 
Again, even when the ball is being thrown, the system comprising Earth, thrower and ball is isolated. The ball thrusts back on the thrower, whose feet thrust downwards on the Earth as it is being accelerated. Momentum, energy and angular momentum for the whole system are again all conserved.
Now we meet a subtlety. If, by isolated, you mean only "energy conserving" then a ball in flight is isolated: the sum of its gravitational potential and kinetic energy is indeed constant. But this is an unusual definition of "isolated".
