Question 2 [3/12]: A train consists of a 400,000-lb locomotive and one hundred 200,000-lb hopper cars. If the locomotive exerts a friction force of 40,000 lb on the rails in starting the train from rest, compute the forces in couplers 1 and 100. Assume no slack in the couplers and neglect friction associated with the hopper cars. 100 99 98 3 21

Question 2 [3/12]: A train consists of a 400,000-lb locomotive and one hundred 200,000-lb hopper cars. If the locomotive exerts a friction force of 40,000 lb on the rails in starting the train from rest, compute the forces in couplers 1 and 100. Assume no slack in the couplers and neglect friction associated with the hopper cars. 100 99 98 3 21

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.79P: The coefficient of rolling resistance between the 30-kg lawn roller and the ground is r=0.1. (a)...

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Situation 02. A crate has a mass of 120kg and the coefficient of static and kinetic friction is 0.60 and 0.50, respectively. The crate starts from rest and the motor exerts a tension T= 1220 + 200t (N). If the elevation of the dock is 30 degrees from the horizontal, What is the velocity of the crate after 1sec? b. Compute the power transmitted after 1sec. COMPLETE SOLUTION OF IMPULSE AND MOMENTUM
Situation 02. A crate has a mass of 120kg and the coefficient of static and kinetic frictionis 0.60 and 0.50, respectively. The crate starts from rest and the motor exerts a tensionT= 1220 + 200t (N). If the elevation of the dock is 30 degrees from the horizontal,a. What is the velocity of the crate after 1sec?b. Compute the power transmitted after 1sec.
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NOTE: Please answer problem #2. Prob#1: Determine the time required that the elevator travels at any instant at a distance of 8 meters. The weight of the elevator is 10,000 N moving downward from rest until its velocity is 15 m / sec. (sec.) Please answer this question only: Prob#2: In Problem 1, determine the force exerted in the cable to support the elevator. (kN)
A crate has a mass of 120kg and the coefficient of static and kinetic friction is 0.60 and 0.50, respectively. The crate starts from rest and the motor exerts a tension T= 1220 + 200t (N). If the elevation of the dock is 30 degrees from the horizontal, a. What is the velocity of the crate after 1sec? b. Compute the power transmitted after 1sec. Pls show diagram
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