Strenght of Materials

16

The hoop stress in a riveted cylindrical shell of diameter (d), thickness (t) and subjected to an internal pressure (`rho`) is (where `eta` = Efficiency of the riveted joint)

A. `(rhod)/(teta)`
B. `(rhod)/(2teta)`
C. `(rhod)/(4teta)`
D. `(rhod)/(8teta)`

17

If the modulus of elasticity for a given material is twice its modulus of rigidity, then bulk modulus is equal to

A. 2C
B. 3C
C. `(2C)/(3)`
D. `(3C)/(2)`

18
 

When a body is subjected to a direct tensile stress (`sigma_x` in one plane accompanied by a simple shear stress (`tau_(xy)`), the minimum normal stress is

A. `(sigma x)/(2) + 1/2 sqrt(sigma _x^2 + 4 tau_(xy)^2)`
B. `(sigma x)/(2) - 1/2 sqrt(sigma _x^2 + 4 tau_(xy)^2)`
C. `(sigma x)/(2) +1/2 sqrt(sigma _x^2 - 4 tau_(xy)^2)`
D. ` 1/2 sqrt(sigma _x^2 + 4 tau_(xy)^2)`

19

When a closely-coiied helical spring of mean diameter (D) is subjected to an axial load (W), the deflection of the spring (`delta`) is given by (where d = Diameter of spring wire, n = No. of turns of the spring, and C = Modulus of rigidity for the spring material)

A. `(WD^3n)/(Cd^4)`
B. `(WD^3n)/(2Cd^4)`
C. `(WD^3n)/(4Cd^4)`
D. `(WD^3n)/(8Cd^4)`

20

The strain energy stored in a hollow circular shaft of outer diameter (D) and inner diameter (d) subjected to shear stress is

A. `(tau^2)/(2C) ((D^2 - d^2)/(D))`x Volume of shaft
B. `(tau^2)/(2C) ((D^2 + d^2)/(D))`x Volume of shaft
C. `(tau^2)/(4C) ((D^2 - d^2)/(D))`x Volume of shaft
D. `(tau^2)/(4C) ((D^2 + d^2)/(D))`x Volume of shaft