[JYSTYLE*]

using Newton's laws, can anyone explain why when you`re
roller skating and two people run into each other, both people
will go the opposite way and not just stay still?

is it because since the net force of the object is disturbed (2nd newton law)
and another force has acted upon it (1st law)? i dont know how to answer
this question throughly. if anyone has an answer, it`ll be really helpful
thanks in advance =)

[tripperazn]

I kinda forgot which # this is, but there is a law that says "Every action has an equal and opposite reaction". This is a simplification from the actual force definition, which is when A exerts force on B, B exerts a force of the same magnitude, but in the opposite direction of the force exerted by A.

The two people colliding on rollerskates exert force on each other during the collision. Refer to the diagram:

-> A x B <-

A and B are the two people involved, with the arrows indicating the direction that they are travelling. "x" is the spot that they are going to meet.

<-AxB->

This is what happens to their direction after they collide. Notice how the directions are reversed? The arrows, you can think of as forces (though that isn't always the case, when they are traveling at constant velocity in a vaccum, there is no force). As the collision occurs the each person exerts force in the direction that they are traveling. Therefore, by Newton's law, there will be a equal force that pushes them back in the reverse direction.