When newton’s third law applies, two interacting objects change each other’s momentum during their interaction: a) either a set ∆t interaction time like two skateboarders pushing off from each other, or b) continuously over time like a gravitational interaction of the moon and earth. the change in momenta is both objects.

The same size for both the objects.

Explanation:

 The newton third law states that "For each and every action, there is equal and the opposite reaction". The newton's statement is basically state that in each interaction, the pair of the forces are mainly acted upon the two given object which is interacting. So, the force of the first object is similar to the second object in this law.

Therefore, In the newtons third law, when the two objects are change their momentum with each other during the interaction then, the change in the momenta for both the object has same size.

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