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141.

The satisfactory method of reclaiming worn out and under sized part subject to fatigue loads is

A.	Repainting	B.	Polishing
C.	Electroplating	D.	Recasting
E.	None of the above

142.

A boiler shell 280 cm diameter and plate thickness 12 mm is subjected to an internal pressure of 1.2 MN/m2. The hoop stress will be

A.	45 N/m2	B.	60 N/m2
C.	135 N/m2	D.	155.5 N/m2
E.	180 N/m2

143.

A thin cylinder contains fluid at a pressure of 30 kg kg/cm2, the internal diameter of the shell is 60 cm and the tensile stress in the material is to be limited to 900 kg/cm2. The shell must have a minimum wall thickness of

A.	1 mm	B.	9 mm
C.	10 mm	D.	12 mm
E.	27 mm

144.

If water in closed pipe freezes, the pipe will

A.	Rupture along a plane perpendicular to the axis of pipe	B.	Rupture zig-zag along the length
C.	Rupture along weakest circumferential section	D.	Rupture in a plane inclined at 45 degree to the longitudinal axis of the pipe
E.	Rupture along a line running longitudinally along the pipe

145.

What should be the thickness of a cast iron pipe 45 cm diameter if it is required to sustain 6 kg/sq cm inside pressure ? The maximum stress in the pipe material being limited to 140 kg/cm2

A.	5 mm	B.	7.5 mm
C.	10 mm	D.	12 mm
E.	15 mm

146.

While designing a shaft pulley and key for a system

A.	Shaft is the weakest member	B.	Pulley is the weakest member
C.	Key is the weakest member	D.	All are designed for equal strength
E.	None of the above

147.

Approximate horse power that can be transmitted by a shaft 60 mm diameter at 180 r.p.m. with permissible shear stress of 850 kg/cm2, would be

A.	30-35	B.	35-50
C.	50-65	D.	65-85
E.	85-95

148.

A solid shaft of 100 mm diameter transmits 100 HP at (450/?) r.p.m. The torque in kg-m on the shaft would be

A.	250	B.	375
C.	500	D.	750
E.	990

149.

In case of ductile materials the theory of elastic failure generally applied is

A.	Maximum principal stress theory	B.	Maximum shear stress theory
C.	Maximum strain theory	D.	Maximum total strain energy theory
E.	Distortion energy theory

150.

In case of brittle material the theory of elastic failure generally applied is

A.	Maximum principal stress theory	B.	Maximum shear stress theory
C.	Maximum strain theory	D.	Maximum total strain energy theory
E.	Distortion energy theory