To begin with, we have reason to expect that it does not matter whether we shoot object 1 towards object 2 or object 2 towards object 1, because we learned in the previous chapter that only relative motion is detectable, and the relative motion is the same in both cases. ISonsider, for instance, what the collision in Figure 3.1 appears like to a hypothetical observer moving along with object 1. at 1 m/s. To him, object 1 appears to be at rest. and it is object 2 that is coming towards him, with a velocity of 1 mfs. To see what the outcome of the collision looks like to him, just add the same 1 m/s to the nal velocities we obtained before: object 1 will end 11p moving at m; = 4/3 m/s, and object 2 would move at 1'2 j = 1/'3 mfs, and we would have a situation like the one shown in Figure 3.2, where both curves have simply been shifted down by 1 m fs: 1 [1115 m v ([1115) t (ms) Figure 3.2: Another example (really the same collision as in Figure 1, 01113.: as soon by an observer initially,r moving to the right at 1 [Ill/5's). Problem 3: Which of the two objects in Figure 3.2 has the largest momentum (in magnitude) after the collision? Select One of the Following: (3) Object 1 (b) Object 2 (c) Neither both have the same momentum J (cl It is impossible to tell