12_Mechanics SolutionInstructors_Sol.Manual-Mechanics_Materials_7e.book_Gere_light.1

12_Mechanics SolutionInstructors_Sol.Manual-Mechanics_Materials_7e.book_Gere_light.1

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 01Ch01.qxd 6 9/25/08 7:49 PM Page 6 CHAPTER 1 Tension, Compression, and Shear Problem 1.2-6 A car weighing 130 kN when fully loaded is pulled slowly up a steep inclined track by a steel cable (see figure). The cable has an effective cross-sectional area of 490 mm2, and the angle a of the incline is 30°. Calculate the tensile stress st in the cable. Solution 1.2-6 Car on inclined track FREE-BODY DIAGRAM OF CAR TENSILE STRESS IN THE CABLE W Weight of car T Tensile force in cable Angle of incline A R1, R2 Effective area of cable Wheel reactions (no friction force between wheels and rails) st T A Wsin a A SUBSTITUTE NUMERICAL VALUES: W A st 130 kN 30° 2 490 mm (130 kN)(sin 30°) 490 mm2 133 MPa ; EQUILIBRIUM IN THE INCLINED DIRECTION © FT T 0 Q+b T W sin a 0 W sin Problem 1.2-7 Two steel wires support a moveable overhead camera weighing W 25 lb (see figure) used for close-up viewing of field action at sporting events. At some instant, wire 1 20° to the horizontal and wire 2 is at an angle is at on angle 48°. Both wires have a diameter of 30 mils. (Wire diameters are often expressed in mils; one mil equals 0.001 in.) Determine the tensile stresses 1 and 2 in the two wires. T2 T1 b a W ...
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online