The reason why we are able to accelerate forward when starting to run is that the striking foot pushes back against the ground and the friction with the ground provides an equal and opposite force forward. What law of motion governs this situation? * Law of Acceleration Law of Interaction Law of Universal Gravitation Law of Inertia

The reason why we are able to accelerate forward when starting to run is that the striking foot pushes back against the ground and the friction with the ground provides an equal and opposite force forward. What law of motion governs this situation? * Law of Acceleration Law of Interaction Law of Universal Gravitation Law of Inertia

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter4: Dynamics: Force And Newton's Laws Of Motion

Section: Chapter Questions

Problem 46PE: Integrated Concepts A basketball player jumps straight up for a ball. To do this, he lowers his body...

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Train Collision and Newtons First Law A group of college students discusses the train collision case study. Use Newtons first law to decide which underlined statements are correct and which are false. Explain your answers. Shannon: This newspaper says that the people who got really hurt were either standing up or sitting in a forward-facing seat. Those people got thrown forward when the train stopped. Avi: Thats why there are seat belts in cars. If you get into a crash, the force can throw you through the windshield. Cameron: There is no force that throws you through the windshield. You fly through the windshield because you are already moving and it would take a force to stop you from going forward. Thats why theres a seat belt. Avi: That doesnt make sense. Because then you would need a force to stop you from flying through the windshield even when you just stop slowly at a red light. Cameron: Thats right, but when you slow down slowly, you dont need such a big force and the car seat can take care of it. Shannon: The seat? I dont think a seat can exert a force. It cant move on its own or hold you. Thats why the people who were sitting forward on the train were hurt. The people who were sitting backward had the back of the seat to block them.
Review. A student, along with her backpack on the floor next to her, is in an elevator that is accelerating upward with acceleration a. The student gives her backpack a quick kick at t = 0, imparting to it speed v and causing it to slide across the elevator floor. At time t, the backpack hits the opposite wall a distance L away from the student. Find the coefficient of kinetic friction k between the backpack and the elevator floor.
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