1350kg car resting on a plane surface with its brakes locked.(adsbygoogle = window.adsbygoogle || []).push({});

Unit vector [tex] e_n = <.231,.923,.308> [/tex] is perpendicular to the surface. The y axis points upwards. The direction cosines of a cable supporting the car are [tex]<-.816,.408,-.408>[/tex] and the tension in the cable is 1.2KN. Determine the magnitude of the normal and friction forces the car's wheels exert on the surface.

This is what I have so far:

[tex]F_f = <.231F_x, .923F_y, .308F_z>[/tex]

[tex]T_{AB} = 1200<-.816, .408, -.408>[/tex]

[tex]W = -(1350)*(9.8)\hat{j}[/tex]

[tex]N = |1200|<.231,.923,.308>[/tex]

[tex]0 = F_f + T_{AB} + N - W[/tex]

But when I solve the equations, I come up with N being 9719N, it is supposed to be about 2500 more.

Thanks!

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# Homework Help: Equilibirum Forces

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