A passenger lurches forward when a moving bus brakes suddenly. Which law or principle best explains this?
Answer and explanation
Correct answer: B. Newton's first law: the passenger tends to keep moving at constant velocity
- Step 1: A body continues in its state of motion unless a net force acts on it; the bus slows but the passenger keeps moving.
Answer
Newton's first law: the passenger tends to keep moving at constant velocity.
Why not the others: Newton's third law: the bus pushes the passenger back: the passenger is not pushed by a reaction force from the bus. The law of conservation of energy: the question is about the tendency of the body to keep its motion. Newton's law of universal gravitation: gravity is not the cause of the forward motion.
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