Question

HELP: When Jane drives to work, she always places her purse on the passenger's seat. By the time she gets to work, her purse has fallen on the floor in front of the passenger seat. One day, she asks you to explain why this happens in terms of physics. What do you say?

Answer 1

a force is a push or pull that acts upon an object as a result of its interaction with another object.  Newtons third law of motion suggests that something standing still will stay that way until another force pushes it.  This applies to Janes bag.  Every time Jane hits the brakes in her car, her bag will move forward until it finally falls off the seat.