A) A rifle is placed on a wooden board. The board is stationary and has frictionless wheels. A heavy piece of wood is placed in front of the rifle. We shoot in this block that accelerates then, after a while, slows down and stops due to friction with the plank. Which of the following statements is true? 1. The board does not move. 2. The moment is not conserved because of the frictional force. 3. The speed of the board is equal to zero immediately after the collision between the ball and block. 4. The board changes its position relative to its starting point. 5. Kinetic energy is conserved because the velocity of the system is equal to zero before and after the collision. B) A block of mass m moves at speed v1. It is subjected to a force of constant friction F. In order to increase its speed from v1 to v2 over a distance d, we must perform a total work expressed by: 1. Fd 2. 1/2(mv22) 3. 1/2m(v22-VI2) 4. 1/2m(v2-V1)2+ Fd 5. 1/2m(v22-V12) + Fd C) A student exerts a force of 12 N to compress a spring over a length of 2.54cm. The constant force required to perform this compression is: 1.0,30 N/m 2. 31 N/m 3. 4,7 N/m 4. 4,7 x 102 N/m 5. 15 N/m

A) A rifle is placed on a wooden board. The board is stationary and has frictionless wheels. A heavy piece of wood is placed in front of the rifle. We shoot in this block that accelerates then, after a while, slows down and stops due to friction with the plank. Which of the following statements is true? 1. The board does not move. 2. The moment is not conserved because of the frictional force. 3. The speed of the board is equal to zero immediately after the collision between the ball and block. 4. The board changes its position relative to its starting point. 5. Kinetic energy is conserved because the velocity of the system is equal to zero before and after the collision. B) A block of mass m moves at speed v1. It is subjected to a force of constant friction F. In order to increase its speed from v1 to v2 over a distance d, we must perform a total work expressed by: 1. Fd 2. 1/2(mv22) 3. 1/2m(v22-VI2) 4. 1/2m(v2-V1)2+ Fd 5. 1/2m(v22-V12) + Fd C) A student exerts a force of 12 N to compress a spring over a length of 2.54cm. The constant force required to perform this compression is: 1.0,30 N/m 2. 31 N/m 3. 4,7 N/m 4. 4,7 x 102 N/m 5. 15 N/m

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter8: Rotational Equilibrium And Dynamics

Section: Chapter Questions

Problem 84AP: A light rod of length 2L is free to rotate in a vertical plane about a frictionless pivot through...

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