Chapter 3

Problem 3.1

3.1 (a) For the hoow shaft and loading shown, determine ihe mximum shsarng stress. (A) Determine the diameter of a solid sha for which the mximum shearing stress in the loading shown ts the same as in part a. C,

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Problem 3.2

3.2 (a) Determine the torque that can be applied ta a &od haft of 3 6-in. ouler diameter withoul exceeding an aliowabie shearing stress of ] O ks, (t) Sove part a, assunting tliat the solid shaft is replaced by a hollow shaft of (lie same mass and of 3.6- in. irmer diameter.

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Problem 3.11

3.11 The torques shown are exerted on pulleys.4, B, and C. Knowing ihat both shaft s are solid, determine the mximum shearing stress in (a) shaft AB, (b) shaft BC.

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Problem 3.12

3,12 The shaftsof ihepullcyassembly shown arelo beredesigned. Knowing that the aliowible shearing stress in each shaft is 6 0 MPa, determine the smallest allowable diameter of (J) shaft AB, (b) shaft BC,O X m

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Problem 3.18

3.18 Shaft AB has a 30-mm diameter and is made of a steel with an allowable shearing stress of 90 MPa, whiie shaft BC ha* a 50-mm diameter and is made o f aa aluminum alloy with an allowable sliearing stress of 60 MPa. Neglecting the eflect of stress concentrations, determine the largest torque T that can be applied at A

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Problem 3.19

3,19 Tbe allowable shearing stress is 100 MPa tu the 36-mm-diamcter steel rod AB and 60 MPa in the 40-mm-diameter rod BC Neglecting the effect of stress concentrations, determine the largest torque that can be appedat^.

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Problem 3.25

3.25 Under normal operating conditions a motor exerts a torque of magnitude T = 150 N m at P. The shafts are made of a steel for which Ihe allowable shearing stress is 75 MPa. Knowing that for the gears r = 200 mm and r 75 mm, determine the required diameter of (a) shaft CDE, (A) shaft FH.F D a

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Problem 3.26

3.26 Under normal operating conditions a motor exerts a torque of magnitude T at F The shafts are made of a steel for which the allowable shearing stress is 85 MPa and have diameter s d = 22 mm and d^ = 20 mm. Knowing tilat r = ISOmmandry - 100 mm, determine ihe largest allowable valu of T .F CDS n y

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Problem 3.27

3.17 The two solid shafts are connected by gears as shown and are made of a steel for which the allowable shearing stress is 8500 psi. Knowing that a torque of magnitude T = 5 kip - in. is applied at C and that tlie assembly is in equibrium, > determine the required diameter of (o) shaft BC, (b) shaft EF.c

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