英语 华氏指数 3.(a) A wire is made of a material to support the we

英语 华氏指数
3.(a) A wire is made of a material to support the weight of a person,calculate the minimum cross sectional area of
the wire that could be used before the wire would definitely break (assume the tensile strength of wire material =
750 MPa ,the weight of a person = 75 Kg and the acceleration due to gravity,g = 10 ms-2) .
(b) Calculate the tensile stress in a rod that is 1 metre in length and is stretched by 1 cm (the rod material has a
Young’s Modulus of E= 10 GPa,1 GPa = 1 x 109 Pascals).
(c) If the rod has a Poisson ratio of 0.5 and a diameter of 2cm calculate by how much the rod thins on being
stretched.
[15 + 5 + 5 = 25 marks]
4.A stress maximum occurs where a lever door handle joins the central spindle at a distance of 1cm from the
central axis of the spindle (the cross sectional area of material at this connection point is 0.2 cm2).A torque of 100
Nm is applied via the door handle but the spindle is locked in position and does not move.
(a) Sketch a diagram illustrating this loading situation.
(b) Calculate the shear stress at the point the door handle joins to the spindle (hint:calculate the force at this point)
(c) Calculate the bending deflection angle of the handle at this joining point assuming the material used has a shear
modulus value G= 28 GPa ( 1 GPa = 1 x 109 Pascals)
[5 + 10 + 10 = 25 marks]
/end of worksheet

翻译吗?3.(a)导线被做材料支持人的重量,计算可能使用导线 的极小的断面面积,在导线确定地将打破之前(假设导线材料抗拉强度= 750 MPa、人的重量= 75公斤和加速度由于重力,g = 10女士2).(b)计算张应力在是1米长和由1 c...