- #1
whynot314
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say a bullet with mass mb and initial speed v0 strikes and becomes embedded in a block of mass mc, which is initially at rest. The coefficient of kinetic friction between the bock and the surface is uk. ( a situation I set up)
my question is, because its an impact problem. Can I ignore the friction force over time and use the conservation of linear momentum. because I can assume it is a non impulsive force in this situation?
Ive done some other problems similar to this where there is a constant force, and it is included. So I figure I can remove it when it is an impact.
G1+[itex]\int^{t2}_{t1}[/itex][itex]\SigmaFdt[/itex]=G2
here is the Problem
[URL=http://s1341.photobucket.com/user/nebula-314/media/20140207_224649_zps5b1d47a5.jpg.html][PLAIN]http://i1341.photobucket.com/albums/o745/nebula-314/20140207_224649_zps5b1d47a5.jpg[/URL][/PLAIN]
my work. I am unsure about how to go from here, If I solve for V. I can't really use vdv=ads because I can't assume constant acceleration. And the solution does not have time in it. but this is impulse/momentum equation. So I am not to sure.
[URL=http://s1341.photobucket.com/user/nebula-314/media/20140207_225157_zpse4356e4f.jpg.html][PLAIN]http://i1341.photobucket.com/albums/o745/nebula-314/20140207_225157_zpse4356e4f.jpg[/URL][/PLAIN]
my question is, because its an impact problem. Can I ignore the friction force over time and use the conservation of linear momentum. because I can assume it is a non impulsive force in this situation?
Ive done some other problems similar to this where there is a constant force, and it is included. So I figure I can remove it when it is an impact.
G1+[itex]\int^{t2}_{t1}[/itex][itex]\SigmaFdt[/itex]=G2
here is the Problem
[URL=http://s1341.photobucket.com/user/nebula-314/media/20140207_224649_zps5b1d47a5.jpg.html][PLAIN]http://i1341.photobucket.com/albums/o745/nebula-314/20140207_224649_zps5b1d47a5.jpg[/URL][/PLAIN]
my work. I am unsure about how to go from here, If I solve for V. I can't really use vdv=ads because I can't assume constant acceleration. And the solution does not have time in it. but this is impulse/momentum equation. So I am not to sure.
[URL=http://s1341.photobucket.com/user/nebula-314/media/20140207_225157_zpse4356e4f.jpg.html][PLAIN]http://i1341.photobucket.com/albums/o745/nebula-314/20140207_225157_zpse4356e4f.jpg[/URL][/PLAIN]
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