Ask Experts Questions for FREE Help !
Ask
    Hiro's Avatar
    Hiro Posts: 19, Reputation: 1
    New Member
     
    #1

    Aug 4, 2008, 01:20 PM
    Newton's 3rd law / instantaneous acceleration
    If for every action there is an equal and opposite reaction then when an object A strikes object B shouldn't the force involved be infinitely reflected between the two objects?

    On the same note, does the opposite reaction bit mean that when an object is acted upon it will move with twice the force it was hit with?


    As for instantaneous acceleration. This name sounds like a misnomer, it seems to me illogical that something can have acceleration that is not measured between 2 points. Can anyone explain this to me?
    Capuchin's Avatar
    Capuchin Posts: 5,255, Reputation: 656
    Uber Member
     
    #2

    Aug 4, 2008, 02:47 PM
    Quote Originally Posted by Hiro
    If for every action there is an equal and opposite reaction then when an object A strikes object B shouldn't the force involved be infinitely reflected between the two objects?
    I'm not sure what you mean here. Can you clarify?

    Quote Originally Posted by Hiro
    On the same note, does the opposite reaction bit mean that when an object is acted upon it will move with twice the force it was hit with?
    Again this is a bit unclear to me. When one object hits another object. Object A produces a force on Object B. The law states that Object B produces the same amount of force on Object A. I suppose, from the point of view of object A, if the force were to all go into velocity, then object B would have twice the applied force. But to an outside observer it's fairly obviouis that this is not so.

    Quote Originally Posted by Hiro
    As for instantaneous acceleration. This name sounds like a misnomer, it seems to me illogical that something can have acceleration that is not measured between 2 points. Can anyone explain this to me?
    This is just to help with the calculation, of course no force is applied instantaneously, because then the impulse (=Ft) would be infinite. It's the same when you assume perfectly spherical objects, or frictionless environments. It's just to help with the calculation, and is a decent approximation to the real world situation.
    Hiro's Avatar
    Hiro Posts: 19, Reputation: 1
    New Member
     
    #3

    Aug 5, 2008, 01:08 PM
    When an object hits another object the 1st object will transfer its kinetic energy to the 2nd object. In turn, newton's 3rd states that the 2nd object will react by acting on the 1st object with the same amount of force.

    However if Newton's 3rd law is true then shouldn't the 1st object react by acting upon the 2nd object with the same amount of force that the 2nd used on it? And so on it goes.
    Capuchin's Avatar
    Capuchin Posts: 5,255, Reputation: 656
    Uber Member
     
    #4

    Aug 5, 2008, 02:00 PM
    Quote Originally Posted by Hiro
    when an object hits another object the 1st object will transfer its kinetic energy to the 2nd object. In turn, newton's 3rd states that the 2nd object will react by acting on the 1st object with the same amount of force.

    However if Newton's 3rd law is true then shouldn't the 1st object react by acting upon the 2nd object with the same amount of force that the 2nd used on it? and so on it goes.
    In a word, no.

    Remember that the collision is instantaneous. The objects come into contact, object a produces a force on object b and object b produces a force on object a, these forces make the objects move apart.

Not your question? Ask your question View similar questions

 

Question Tools Search this Question
Search this Question:

Advanced Search

Add your answer here.


Check out some similar questions!

Newton's 3rd Law [ 2 Answers ]

When a horse pulls on a cart, the cart pulls on the horse with an equal but opposite force. How is the horse able to pull the cart?

Newton's Second Law [ 2 Answers ]

I need help understanding how to solve this problem F=ma if: how much force is needed to acceleratea 1000-kg car at a rate of 3m/s-squared I don't understand the steps involved. Thanks for your help.

Finding the instantaneous speed [ 1 Answers ]

in a dotted line graph, the x axis is time in seconds, and the y axis is distance in meters. The slope of the line is 3/2, how do I find the instantaneous speed?

Substituting derivative of acceleration for acceleration [ 1 Answers ]

Can the derivative of acceleration be subsituted for a in f=ma?


View more questions Search