Hey. Quick question. If we have a compressed air tank of 550 kPa with a opening area of 0.25 cm^2, would the force provided just be P*A so it'd just be 550 * 0.25 (with appropriate conversions to metres and pascals etc). We are looking for the force that'd be provided to a model car that the tank (from a paintball gun) is attached to. ??? Or is it something a little bit more complicated than that. This isn't a homework question where we need an exact answer, we only need to estimate it.