$A$ wire of length $40 \text{ cm}$ is stretched by $0.1 \text{ cm}$. The strain on the wire is

According to Hooke's law,force is proportional to:

Consider a long steel bar under a tensile stress due to force $F$ acting at the edges along the length of the bar (as shown in figure). Consider a plane making an angle $\theta$ with the length. What are the tensile and shearing stresses on this plane?
$(a)$ For what angle is the tensile stress a maximum?
$(b)$ For what angle is the shearing stress a maximum?

What is stress? Write its unit and dimensional formula.

$A$ wire can be broken by applying a load of $20 \, kg$ weight. The force required to break the wire of twice the diameter is .......... $kg \, wt$.

The material which practically does not show elastic after effect is