problems for practice

PROBLEMS FOR PRACTICE

1. Find the driving torque T applied to link 2, for the slider crank mechanism shown in Fig.10.8. AB = 75 mm; BC 350 mm. 

[Ans. 100 N•m]

2. For the four bar linkage of Fig.10.9, find all the constraint forces and the required driving torque for equilibrium of the system.

AB = 171 mm; BC = 457 mm; CD = 320 mm; AD = 194 mm

[Ans. F14 = 396 N; F12 = F23 = F43 = F32 = F34 = 147.3 N; T = 20.68 Nm]

3. Find the torque must be applied to link 2 of the four bar linkage shown in Fig. 10.10, to maintain static equilibrium.

AB = 90 mm; BC = 152 mm; CD = 152 mm; AD = 51 mm; DE = 98 mm

[Ans. 9.92 Nm, clockwise]

4. For the static equilibrium of the four bar mechanism shown in Fig.10.11, find the value of force S applied to link 2 as only its direction is given.

AB = 150 mm; AD = 560 mm; DC = 300 mm; AB = 300 mm; BC= 305 mm; BF = 160 mm = and CE = 140 mm.

[Ans. 2060 N]

5. The dimensions of a four bar mechanism are: AB = 400 mm; BC = 600 mm; CD = 500 mm; AD = 900 mm; and DAB = 60°. AD is the fixed link. E is a point on link BC such that BE = 400 mm and CE = 300 mm (BEC clockwise). A force of 150 45° N acts on DC at a distance of 250 mm from D. Another force of magnitude 100180° N acts at point E. Find the required input torque on link AB for static equilibrium of the mechanism. 

[Ans. 0.35 N•m, clockwise]

6. In a four-link mechanism shown in Fig.10.12, torque T3 and T4 have magnitudes of 30 N•m and 20 Nm respectively. The link lengths are AD = 800 mm, AB = 300 mm, BC = 700 mm. For the static equilibrium of the mechanism, determine the required input torque T2. 

[Ans. 16 N•m anticlockwise]

7. For the static equilibrium of the quick-return mechanism shown in Fig.10.13, find the required input torque T2 for a force of 3500 N on the slider. Angle of EB with the vertical is 70°. The impending motion of the slider is to the left.

[Ans. 644 N•m anticlockwise]