Solution to Problem 350 | Helical Springs

Problem 350
As shown in Fig. P-350, a homogeneous 50-kg rigid block is suspended by the three springs whose lower ends were originally at the same level. Each steel spring has 24 turns of 10-mm-diameter on a mean diameter of 100 mm, and G = 83 GPa. The bronze spring has 48 turns of 20-mm-diameter wire on a mean diameter of 150 mm, and G = 42 GPa. Compute the maximum shearing stress in each spring using Eq. (3-9).
 

Bar supported by three springs

 

Solution to Problem 347 | Helical Springs

Problem 347
Two steel springs arranged in series as shown in Fig. P-347 supports a load P. The upper spring has 12 turns of 25-mm-diameter wire on a mean radius of 100 mm. The lower spring consists of 10 turns of 20-mm diameter wire on a mean radius of 75 mm. If the maximum shearing stress in either spring must not exceed 200 MPa, compute the maximum value of P and the total elongation of the assembly. Use Eq. (3-10) and G = 83 GPa. Compute the equivalent spring constant by dividing the load by the total elongation.
 

347-two-springs-in-series.jpg

 

Solution to Problem 340 | Torsion of thin-walled tube Jhun Vert Tue, 04/21/2020 - 02:34 pm

Problem 340
A tube 2 mm thick has the shape shown in Fig. P-340. Find the shearing stress caused by a torque of 600 N·m.
 

Oval thin-walled tube

 

Solution to Problem 339 | Torsion of thin-walled tube Jhun Vert Tue, 04/21/2020 - 02:32 pm

Problem 339
A torque of 450 lb·ft is applied to the square section shown in Fig. P-339. Determine the smallest permissible dimension a if the shearing stress is limited to 6000 psi.
 

Square thin-walled tube

 

Solution to Problem 338 | Torsion of thin-walled tube Jhun Vert Tue, 04/21/2020 - 02:30 pm

Problem 338
A tube 0.10 in. thick has an elliptical shape shown in Fig. P-338. What torque will cause a shearing stress of 8000 psi?
 

Figure P-338 | Elliptical thin-walled tube