work, = mv; -mv; 13.1 1-2 where m is the mass of the object and V, and V, are the speed of the object at positions 1 and 2, respectively. To better demonstrate Equation (13.1), consider the following example. When you push on a lawn mower, which is initially at rest, you perform mechanical work on the lawn mower and move it, consequently changing its kinetic energy from a zero value to some nonzero value. (km ){ 1h }1000 m 90 h {3600 s jl 1 km V, = V 25 m initial V2 = V. = 0 tinal work, , = (force)(distance) = -mV? --mv? (force)(100 m) = 0 -;(1400 kg)|25 kel/25 force = -4375 N

work, = mv; -mv; 13.1 1-2 where m is the mass of the object and V, and V, are the speed of the object at positions 1 and 2, respectively. To better demonstrate Equation (13.1), consider the following example. When you push on a lawn mower, which is initially at rest, you perform mechanical work on the lawn mower and move it, consequently changing its kinetic energy from a zero value to some nonzero value. (km ){ 1h }1000 m 90 h {3600 s jl 1 km V, = V 25 m initial V2 = V. = 0 tinal work, , = (force)(distance) = -mV? --mv? (force)(100 m) = 0 -;(1400 kg)|25 kel/25 force = -4375 N

Engineering Fundamentals: An Introduction to Engineering (MindTap Course List)

5th Edition

ISBN:9781305084766

Author:Saeed Moaveni

Publisher:Saeed Moaveni

Chapter18: Mathematics In Engineering

Section: Chapter Questions

Problem 23P

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