A collision experiment is done on a horizontal table kept in an elevator. Do you expect a change in the results if the elevator is accelerated up or down because of the non-inertial character of the frame?

You are waiting for a train on a railway platform. Your three-year-old niece is standing on your iron trunk containing the luggage, why does the trunk not recoil as she jumps off on the platform?

In a head-on collision between two particles, is it necessary that the particles will acquire a common velocity at least for one instant?

Two bodies make an elastic head-on collision on a smooth horizontal table kept in a car. Do you expect a change in the result if the car is accelerated on a horizontal road because of the non-inertial character of the frame? Does the equation “Velocity of separation = Velocity of approach” remain valid in an accelerating car? Does the equation “final momentum = initial momentum” remain valid in the accelerating car?

If the total mechanical energy of a particle is zero, is its linear momentum necessarily zero? Is it necessarily nonzero?