Question

Why do you fall in the forward direction when a moving bus brakes to a stop and fall backwards when it accelerates from rest?

Answer 1

• Everybody tries to maintain their state of motion or rest. If a body is at rest, it tries to remain at rest. If a body is moving, it tries to remain in motion. In a moving bus, a passenger moves with the bus. As the driver applies brakes, the bus comes to rest. But the passenger tries to maintain his state of motion. As a result, forward force is exerted on him.
• Similarly, the passenger tends to fall backwards when the bus accelerates from rest. This is because when the bus accelerates, the passenger's inertia tends to oppose the bus's forward motion. Hence, the passenger tends to fall backwards when the bus accelerates forward.