Question

Question 3 [14 marks total) (Units of X3 - Nm): Two shafts are fabricated from steel with a diameter of 20 mm and have a shear modulus of elasticity of 75 GPa. The diameter of gear D is 150 mm and the diameter of gear F is 100 mm. The shafts are supported by bearings at C, H, and Ewhich allow free rotation. Two external moments are applied to the system. An external moment X3 is applied at point B and an external moment of 60 Nm is applied on gear G. Assuming the assembly is fixed at point A, calculate the angle of twist at point H. Calculate/Answer: (A) Torque at Gear F [2 marks] (B) Torque at Fixed End A [4 marks) (C) Angle of Twist at point H [8 marks] 250 mm 750 mm А X3 B с 60 Nm H 200 mm G 250 mm F 200 mm

X3= 100 Nm

Answer 1

90 Nm B. GONm conm Am HR G AD. To TO B А TA=XBt To - 100+ 90 TA = 190 Nm c] Angle of twist at point it ople + (Totxz)X LAB, (ToxLBO GT GJ

= 190 x 0.25 90 x 0.75 + 750 x 109 x TV x (0.024 32 75 x 10 x 4 x Co oz) 32 0.0976 rad De Dj Ve Dp X 야 A O. 9976 100 -0. 146 rad Hla + + oxle G % GOXO.25 -0.146 75x10% (roos! - 0.1332 radiany H/A