The particle will be rendered still because of the Newton’s 1st law of motion states that a body will continue to move on forever until contacted by an equal and opposite force. The same case has been produced here and it is justifying the law. If the Force has another direction and magnitude than 10 N then the body will continue to move on in the direction of the greater force.
Here we can see there is no external force acted on a two masses when we consider the motion. If there is no external forces then momentum is conserved.
yes, because you guy's are moving in a car. because if you think about it, your parents are driving, but the cars moving so basically you guys would be moving.