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131.

The value of Young's modulus of elasticity in ascending order for glass, lead, phosphor bronze, steel and wood is

A.	Wood, phosphor bronze, lead glass steel	B.	Wood, glass, phosphor bronze, lead steel
C.	Wood, glass, lead, phosphor bronze, steel	D.	Wood, lead, glass, phosphor bronze, steel
E.	Wood, phosphor bronze, glass, lead, steel

132.

The average values of modulus of rigidity for aluminium brass, copper and steel in descending order is

A.	Aluminium, brass, copper, nickel and steel	B.	Aluminium, copper, brass, nickel and steel
C.	Aluminium, nickel, brass, copper and steel	D.	Aluminium, brass, nickel, copper and steel
E.	Aluminium, copper, nickel, brass and steel

133.

In a gas turbine rotor a radial stress of 300 kg/sq cm tensile and 500 kg/sq cm tangential stress have been found at a point. The maximum shear stress at this point would be

A.	750 kg/sq-cm	B.	500 kg/cm2
C.	300 kg/cm2	D.	250 kg/cm2
E.	595 kg/cm2

134.

In a ball bearing a ball is subjected to

A.	Compressive stress	B.	Tensile stress
C.	Shear stress	D.	Cyclic stress or fatigue
E.	None of the above

135.

Resistance to fatigue of a material is measured by

A.	Youngs modulus	B.	Modulus of rigidity
C.	Electricity parameters	D.	Elastic limit
E.	Endurance limit

136.

Resilience of material should be considered when it is subjected to

A.	Fluctuating load	B.	Wear and tear
C.	Shock loading	D.	Any of the above
E.	None of the above

137.

A unknown weight falls through 1 cm on a collar rigidly attached to the lower end of a vartical bar 3 cm long and 6 cm2 in section. If the maximum instantaneous extension is 2 mm the value of stress would be

A.	500 kg/cm2	B.	667 kg/cm2
C.	1000 kg/cm2	D.	1333 kg/cm2
E.	1500 kg/cm2

138.

With a punch for which the maximum crushing stress is 4 times the maximum shearing stress of the plate, the biggest hole that can be punched in the plate would be of diameter equal to

A.	1/4 x thickness of plate	B.	1/2 x thickness of plate
C.	Plate thickness	D.	2 x plate thickness
E.	4 x plate thickness

139.

The fatigue limit of a material

A.	Is greatly decreased by poor surface conditions	B.	Is improved if there is rough surface
C.	Is independent of surface conditions	D.	Surface defects which extend upto core have no influence of fatigue limits
E.	None of the above

140.

Which process will improve the fatigue life of a part?

A.	Electroplating	B.	Chemical coating
C.	Electrocoating	D.	Polishing
E.	Shot peening