Strenght of Materials

21

The longitudinal stress in a riveted cylindrical shell of diameter (d), thickness (t) and subjected to an internal pressure (p) is

A. `(pd)/(tn)`
B. `(pd)/(2tn)`
C. `(pd)/(4tn)`
D. `(pd)/(8tn)`

22
When the retained material is subjected to some superimposed or surcharged load, the total horizontal pressure due to surcharged load is (where p = Intensity of the supercharged load)
A. `p xx (1 - sin phi)/(1 + sin phi)`
B. `p xx (1 + sin phi)/(1 - sin phi)`
C. `p xx (1 - cos phi)/(1 + cos phi)`
D. `p xx (1 +cos phi)/(1 - cos phi)`

23

When a body is subjected to a direct tensile stress (`sigma`) in one plane, then normal stress on an oblique section of the body inclined at an angle `theta` to the normal of the section is

A. `sigma cos theta`
B. `sigma cos^2 theta`
C. `sigma sin theta`
D. `sigma sin^2theta`

24

The change in length due to a tensile or compressive force acting on a body is given by (where P = Tensile or compressive force acting on the body, l = Original length of the body, A = Cross-sectional area of the body, and E = Young's modulus for the material of the body)

A. `(P.l.A)/(E)`
B. `(P.l)/(A.E)`
C. `(E)/(P.l..A)`
D. `(A.E)/(P.l)`

25
In a leaf spring, the deflection at the centre is


A. `(wl^3)/(8Enbt^3)`
B. `(wl^3)/(4Enbt^3)`
C. `(3wl^3)/(8Enbt^3)`
D. `(wl^3)/(2Enbt^3)`