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251.

A beam of uniform strength will have at every cross-section

A.	same deflection	B.	same stiffuess
C.	same bending moment	D.	same bending stress

252.

An underground pipeline is laid in spring at 35?C. If the pipe is unable to contract, during winter when temperature drops to 5?C, the pipe will be under

A.	hoop stress	B.	Compressive stress
C.	hoop and compressive stresses	D.	tensile stress

253.

A portion of a beam between two sections is said to be in pure bending when there is

A.	constant bending moment and constant shear force	B.	constant shear force and zero bending mement
C.	constant bending moment and zero shear force	D.	zero bending moment and zero shear force

254.

A mild steel flat 3 m long 150 mm wide and 15 mm thick carries an axial tensile load of 150 kN. If the value of u for mild steel is 0.3, it can be concluded that

A.	length, width and thickness all will elongate	B.	length and width will increase but thickness will decrease
C.	length and thickness will increase but width will ecrease	D.	length will increase but width and thickness will decrease

255.

Laminated springs are generally

A.	loaded at ends and supported at centre	B.	loaded at centre and supported at ends
C.	loaded as well as supported at centre	D.	loaded as well as supported at ends

256.

Force required to punch a 15 mm hole in a mild steel pipe 5 mm thick, when ultimate shear stress of the plate is 500 N/mm2, will be nearly

A.	78 kN	B.	98 kN
C.	118 kN	D.	158 kN

257.

The effect of arching a beam is to

A.	increase the shear force	B.	reduce the shear force
C.	reduce the bending moment throughout	D.	increase the bending moment throughout

258.

According to Rankine's theory of failure, elastic failure occurs

A.	When the minor principal stress is equal to the elastic limits value in a simple tension test	B.	When the greatest principal stress reaches the elastic limit value in simple tension test
C.	When the greatest principal stress is equal to the stress corresponding to the upper yield limit in a tension test	D.	None of the above

259.

According to Von Mises theory, the elastic failure occurs

A.	When the shear strain energy is least	B.	When shear strain equals 50% of the value of tensile strain at elastic limit in a simple tension test
C.	When the shear strain energy per unit volume in the stressed material equals shear strain energy per unit volume at the elastic limit in a simple tension test	D.	None of the above

260.

For a shear force to be uniform throughout the span of a simply supported beam, it should be subjected to

A.	a couple at mid span	B.	a couple at any point on the span
C.	a uniformly distributed load	D.	two concentrated loads spaced at third points