For a rectangular cross section
Max. Shear stress = 3/2 [F/A ] 2 = 3/2 [w/200 � 300].
w = 80 kN.

A leaf spring used to absorb shocks and vibrations and springs in brakes and clutches are invariably used in order to apply forces.

An electrical resistance strain gauge is a device for measuring normal strains on surface of a stressed object. The gauges are small (less than half inch) made of wires that are bonded on surface of object. We can use transformation equations for plane strain to calculate strains in various directions.

In rectangular section,
The shear stress at a distance ?y ? from NA = 6F/bd³ � u (u = d²/4-y)
The maximum shear stress occurs at a neutral axis, in above equation when y is equal to zero. q is max. Hence shear stress topmost fibre of rectangular section is zero.

Poisons ratio varies between 0.1 for high strength concrete and 0.2 for weak concrete. Usually it is taken as 0.15 for strength design and 0.2 for serviceability conditions.

In a steel section, junction between flange and web is known as fillet. The connections solve issues of complex geometry for joining members of a central hub while y provide standard connection through out. They are not readily available.

D = 100m
y = 50 mm
R = 10 � 10³mm
By equation of flexure; E/R = f/y
f=E/R �y
= 2�10⁵/ 100 � 10³� 50
= 100 N/mm².

b = 100mm
h = 150 mm
Moment of inertia about centroid Axis = bh³ / 36.
= 100 �150³/ 36
= 9.37�10⁶mm⁴.

According to Indian Standards 456-2000 The modular ratio (m) = 280/3� cbc, For M20; compressive bearing capacity in concrete = 7 N/mm² & tensile strength = 330 N/mm².
Modular ratio (m) = 280/21 = 13.33.

For a triangular section subjected to shear force shear stress in neutral axis is
Shear stress at NA = 4/3 [Average shear stress].
= 4/3 [F/0.5 bh] = 8F / 3bh.