50. If the shear force along a section of a beam is zero, the bending moment at the section is
A. zero
B. maximum
C. minimum
D. average of maximum-minimum

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51. Hooke's law states that stress and strain are
A. directly proportional
B. inversely proportional
C. curvilinearly related
D. none of these.

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52. A cantilever beam rectangular in cross-section is subjected to an isolated load at its free end. If the width of the beam is doubled, the deflection of the free end will be changed in the ratio of
A.8
B. 1/8
C. 1/2
D.2

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53. If the length of a cantilever carrying an isolated load at its free end is doubled, the deflection of the free end will increase by
A.8
B. 1/8
C. 1/3
D.2

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54.  If the width of a simply supported beam carrying an isolated load at its centre is doubled, the deflection of the beam at the centre is changed by
A. 2 times
B. 4 times
C. 8 times
D. 1/2 times

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55. If the width of a simply supported beam carrying an isolated load at its centre is doubled, the deflection of the beam at the centre is changed by
A. 1/2
B. 1/8
C.2
D.8

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56. If the depth of a simply supported beam carrying an isolated load at its centre, is doubled, the deflection of the beam at the centre will be changed by a factor of
A.2
B. ?
C.8
D. 1/8

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