Projectile motion involving mass

AI Thread Summary
When analyzing projectile motion with varying mass, the horizontal distance traveled by an object shot at a constant velocity remains the same regardless of mass, assuming no air resistance. The horizontal component does not experience acceleration, keeping the initial velocity constant, while the vertical component is affected by gravity, which accelerates all masses equally. If two projectiles are fired at the same velocity, the heavier one may travel farther due to differences in aerodynamics, but this requires consideration of drag forces. The discussion highlights the complexity of incorporating drag, as two objects with the same mass but different shapes will behave differently in flight. Thus, simplifying these calculations without the drag equation is challenging.
Glype11
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If the only variable that is changed is mass. What equation would I use to find the distance an object travels that is shot horizontally at a velocity (v) and I would like to be able to calculate the change in velocity?
 
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What is the mechanism by which the mass changes? It makes a big difference exactly how this happens.
 
If "an object travels that is shot horizontally at a velocity (v)", any object shot at velocity (v) will travel the same horizontal distance (neglecting air resistance). The horizontal component of travel experiences no acceleration so the initial velocity (v) remains constant.
The vertical component is experiencing a downward acceleration due to gravity. This acceleration is the same for any mass object so they reach the ground together. Like dropping a basketball and a medicine ball at the same time - they reach the ground together.
If the mechanism that shoots the first object remains the same, then shoots a larger mass object, this second object will not have "velocity (v)" to begin with. Is this what you mean?
 
The case I had in mind, was comparing two projectiles fired at the same velocity, the heavier one will travel farther.
I know it comes down to aerodynamics. I wanted to see if there was a more simplified way of solving these types of problems rather starting with the drag equation.
 
If you want to include the drag than there is no simple answer. Two objects with the same mass but different shapes will behave differently.
 
I have recently been really interested in the derivation of Hamiltons Principle. On my research I found that with the term ##m \cdot \frac{d}{dt} (\frac{dr}{dt} \cdot \delta r) = 0## (1) one may derivate ##\delta \int (T - V) dt = 0## (2). The derivation itself I understood quiet good, but what I don't understand is where the equation (1) came from, because in my research it was just given and not derived from anywhere. Does anybody know where (1) comes from or why from it the...
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