How you may ask? And which law did I break? I believe I broke Newton's Third Law of Motion. As for the how, read on.
I was playing football today. (The game itself was interesting with the amount of lucky lateral passes that were made.) At one point I read a pass and moved to intercept the receiver. The receiver catches the ball and turns to run, but I'm there to stop him. Now here's where the physics come into play.
Let's compare the two objects: Designate me as S1 and the receiver as S2. S1 is 178 lbs and 5'8", S2 is 160lbs and 5'6". Let's convert that to SI. S1 would be 80.74kg and 172cm, S2 would be 72.57kg and 167.64cm. In theory S1 is a larger mass than S2. S1 is at full speed and slowing down and S2 is beginning to accelerate. S1 has an acceleration of 3.35 m/s (based on an eight minute mile), let's say S2 has an acceleration of 3 m/s (remember S2 did not have the opportunity to reach full velocity). According to the equation
F=ma, S1 has a force of 270.48N and S2 a force of 217.71N. That is a difference of 52.77N.
Therefore we have S1(270.48N)--><--S2(217.71N). Now being a lager mass and having more Force you would think the reaction from the collision would have resulted in S2 being propelled backward. However, that was not the case. I was the one propelled backward flat on my back with my glasses going flying. S2 went backwards only because he was dazed from hitting his head on my chest.
So, my conclusion, the Laws of Physics can be broken.
Comments (6)
well, that was a nice read. however, i say it depends how the mass is distributed in S1 vs. S2 (rolled into a ball, straight perpendicular to the ground or some variation) and at what particular angle both objects of mass struck each other that would affect the resting places resulting in the collision
i thought for a moment you were about to tell us you were suspended in the air... like you achieved flying or levitation
@slamjoe - Well, I did fly...I left the ground.
I hope you glasses (and body) weren't broken too.
Hehe, thas funny man. Glad you guys getting out there though. I feel like the only exercise I getting in this town is walking up and down hills. :/
Something's off there though... the units for a are m/s^2, and a 52.44 N is only about 10 lbs of force difference and that's way, way less than what sent u flying, man, unless it wuz the holy spirit, hehe. Don't forget too that in collisions, it's not energy or force that's conserved, but momentum. m1a * v1a+m2a*v2a = m1b *v2b + m2b*v2b, those being vectors too.
@DaMoon - Well, I may have over simplified things a little. And it has been a long time since I studied physics.
i didn't know that the new york times reads your blog.
the physics of 'the hit'