99. A steel rod 1 metre long having square cross section is pulled under a tensile load of 8 tonnes. The extension in the rod was 1 mm only. If Esteel = 2 x 106 kg/cm2, the side of the rod, is

A. 1 cm

B. 1.5 cm

C. 2 cm

D. 2.5 cm.

100. There are two hinged semicircular arches A, B and C of radii 5 m, 7.5 m and 10 m respectively and each carries a concentrated load W at their crowns. The horizontal thrust at their supports will be in the ratio of

A. 1 : 1 1/2 : 2

B. 2 : 1 1/2 : 1

C. 1 : 1 : 2

D. none of these.

101. The horizontal thrust on the ends of a two hinged semicircular arch of radius R carrying

A. a uniformly distributed load w per unit run over its right half span, is

B. a uniformly distributed load w per unit run over its entire span is ?4

C. a distributed load varying from zero at the left end to w per unit horizontal run at the right end, is ?2 ?wR

D. all the above.

102. A two hinged parabolic arch of span 1 and rise h carries a load varying from zero at the left end to w per unit run at the right end. The horizontal thrust is

A. 50 t

B. 75 t

C. 100 t

D. 125 t

103. The locus of reaction of a two hinged semi-circular arch, is

A. straight line

B. parabola

C. circle

D. hyperbola.

104. In plastic analysis, the shape factor for rectangular section, is

A.1.4

B.1.5

C.1.6

D. 1.7.

105. In plastic analysis, the shape factor for a triangular section, is

A.1.5

B.1.34

C.2.34

D. 2.5.

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