Was Air Resistance Noticeable?
Air resistance was noticeable in the course of the projectile's motion. This was seen in the y (altitude) position vs time graph since the objects motion isn't completely symmetrical. When the y position vs time graph is completely symmetrical, it means that as it travels, the object can descend with the same forces acting on it as it ascended. However, because air resistance is proportional to velocity, as velocity increases, the air resistance will as well which will make the descent steeper than when it s ascending, hence not symmetrical. Since the graph shows a curve that isn't completely symmetrical,air resistance was in the equation. (the descend shows a steeper slope since air resistance increases). We could also see that air resistance was noticeable with the Velocity x component vs time as our evidence. This graph (below) tells us that air resistance is there after taking into account of the flaws of tracker since the graph for no air resistance would look like a constant line. This line on the other hand is far from, indicating that air resistance is indeed noticeable.
Was Energy Conserved?
Energy wasn't conserved within the object. Theoretically, we could argue that it was since the Law of Conservation of Energy states that energy couldn't be created nor destroyed. This isn't what we want to answer in this question. We want to answer if the projectile's energy is conserved which could be deduced in our Potential Energy vs Time, Kinetic Energy vs Time, and most simply, the Total Mechanical Energy vs Time graphs. These three graphs are shown to the right in a slideshow format. The easiest way of finding out if energy was conserved is by looking at Total ME vs Time graph and looking to see if it was constant, zero slope. Since it obviously isn't, then the energy wasn't conserved. We could also compare the PE and Kinetic Energy vs Time graphs. If energy was conserved then the graphs would look like opposite shapes flipped over a horizontal lines, but because they don't, energy isn't conserved.
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Was Momentum Conserved?
Momentum was not conserved in the course of the projectile's motion. The formula for momentum is below.
P = mv
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As you can see, velocity is the main deciding factor in what momentum is. Mass will stay constant but the velocity of the object in the x or y component will decide if the momentum is conserved. For momentum to be conserved, the initial momentum has to equal the final, which since the mass is the same, means that the initial velocity must equal the final. If this holds true, then the overall slope, from initial to final is zero, and momentum is really conserved. However, momentum wasn't conserved since both x initial velocity and x final velocity and y initial velocity and y final velocity are different from one another. This means momentum doesn't have a slope of zero and wasn't conserved. Refer to the graphs to the left to further to better understand this.
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