Newton's 3rd law and its affect

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In a bike crash against a metal fence, both the bike and the fence exert equal and opposite forces on each other, as stated by Newton's 3rd law. However, the difference in mass and material properties leads to different responses; the bike, being more massive, may not deform significantly, while the fence can bend due to its structural limitations. The discussion highlights that the ability of materials to withstand force varies, affecting how they respond during collisions. Additionally, the forces act on different bodies, which is crucial in understanding the resulting damage. The interaction illustrates the complexities of force application in real-world scenarios.
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Homework Statement


When a bike crashes into a metal fence why does the fence bend when the magnitude of the forces that they exert upon each other are the same?


Homework Equations



FAB = -FAB

The Attempt at a Solution



I think this is becuase the bike has more mass than the fence... but i am not sure how this is applied.
 
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no f=ma so the mass is already accounted for, should certain materials or apparatuses be able to withstand more force than others?
 
and you also have to remember that the opposite forces work on different bodies
 
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
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