balloon fig newton's

newtons first law plays into the action of the balloon in several ways.  the balloon obviously will not move without a force acting on it.  however the balloon is at the mercy of any small breeze that is present.  since the balloon has such a small mass in comparison to the surface area it is very easily affected by the force applied to it by a small breeze.  none the less, if the balloon could function in a completely still environment once it over came its static inertia it would travel in a straight line.  

the second law is the one that caused us the most substantial challenge.  the force needed to set the balloon in motion must be enough to over come the acceleration due to gravity that is acting on it.  in order for this to happen the envelope of the balloon has to have a large enough volume and a significant enough rise in heat to create enough bouncy to lift the entire contraption.  one of the complications that happened repeatedly was that we were not getting a large enough rise in heat to lift the entire balloon, however it was still very susceptible to breeze moving it horizontally, and setting it on fire. 

the third law is probably the most tricky in regard to this project, in that the actual force creating lift is the cooler atmosphere pushing against the warm envelope.  although this principal is actually quite common, particularly in air bubbles rising in water and being able to use a straw to drink.  the colder air is denser then the warm air, as the warm air becomes hotter it becomes progressively less dense, making it still lighter then the surrounding cold air.  at this point the pressure of the cooler air pressing in on the balloon can become significant enough to cause the lighter air to be forced upward.  in this case the envelope is exerting force back onto the surrounding air, which is exerting force on the balloon in terms of pressure.