Question

amy gets up from her seat on a train to move closer to the front. just as she begins to walk forward, the train stops at a station. what is the best explanation of what happens to amy? while amy is walking, her body is in motion. when the train stops, because shes not buckled in, amy continues to move forward due to inertia. while amy is walking, her body is in motion, but as the train stops, it exerts a force on amy opposite to the direction she is walking, causing her to stop as well. while amy is walking, she is in motion due to the force of repulsion. when the train stops, she is catapulted forward due to the trains stronger force of attraction. while amy is walking, her body is in motion. when the train stops, an unbalanced force accelerates her body backward.

Explanation:

According to Newton's first law of motion (law of inertia), an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force. Amy is walking and in motion relative to the train. When the train stops, there is no force to immediately stop her body's forward - motion, so she continues moving forward due to inertia.

Answer:

While Amy is walking, her body is in motion. When the train stops, because she's not buckled in, Amy continues to move forward due to inertia.