The breaking stress of a wire depends upon

The elasticity of Invar:

Explain tensile stress and compressive stress.

Two equal and opposite forces each $F$ act on a rod of uniform cross-sectional area $a$ as shown in the figure. The shearing stress on the section $AB$ will be

$A$ tangential force of $100 \,N$ is applied on the top face of a cubic block of side $0.1 \,m$. If the top face is displaced by $0.02 \,cm$ relative to the bottom face,what is the tangential strain?

What is strain? Explain longitudinal strain $(\varepsilon)$.