Strength of Material Sheet 20
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1) Question.
A steel bar of length is fixed at both ends at . The coefficient of thermal expansion is
and the modulus of elasticity is
Answer. -
2) Question.
A mild steel bar is in three parts, each long. The diameters of parts , and are , and
Answer.3) Question.A steel cable of diameter is used to lift load of . Given that, and the
length of the cable is , the elongation of the cable due to the load
Answer.4) Question.Consider the following statements :
In a uni-dimensional stress system, the principal plane is defined as one on which the
1. shear stress is zero
2. normal stress is zero
3. shear stress is maximum
4. normal stress is maximum
of these statements
Answer.5) Question.For the design of a cast iron member, the most appropriate theory of failure is
Answer.6) Question.At a point in a steel member, the major principal stress is 2000 kg/cm² and the minor principal stress is compressive. If the uni-axial tensile yield stress is 2500 kg/cm², then the magnitude of the minor principal stress at which yielding will commence, according to the maximum shearing stress theory, is
Answer.7) Question.For ductile materials, the most appropriate failure theory is
Answer.8) Question.A three hinged parabolic arch rid is acted upon by a single load at the left quarter point. If the central rise is increased and the shape of arch altered to segmental without changing the other details, the horizontal thrust will
Answer.9) Question.The stress below which a material has a high probability of not failing under reversal of stress is known as
Answer.10) Question.The property of metal which allows it to deform continuously at slow rate without any further increase in stress is known as
Answer.11) Question.The phenomenon of decreased resistance of a material to reversal of stress is called
Answer.12) Question.Impact test enables one to estimate the property of
Answer.13) Question.The specimen in a Charpy impact test is supported as a
Answer.14) Question.If the depth of a beam of rectangular section is reduced to half, strain energy stored in the beam becomes
Answer.15) Question.Two identical bars, one simply supported and other fixed at ends, are acted upon by equal loads applied at the midpoints.
The ratio of strain energy stored in the simply supported beam and the fixed ended beam is
Answer.16) Question.Two circular bars and of same material and same length are of diameters and respectively. The bars are
subjected to the same torque T. The ratio of strain energies stored in the bars and is proportional to
Answer.17) Question.A steel rod of cross sectional area equal to 1000 mm² is 5 m long. If a pull of 100 kN is suddenly applied to it, then the
maximum stress intensity will be
Answer.18) Question.A rectangular block of size is subjected to a shear stress of . If
modulus of rigidity of material is , strain energy stored will be
Answer.19) Question.Strain energy stored in a member is given by
Answer.20) Question.Proof resilience is the maximum energy stored at
Answer.
