For the tangential stress on the cross-section $PQRS$ to be maximum,$\theta = $ ....... $^o$

Name the property of a material by which it opposes the deformation.

The unit of stress is:

What are elastomers? Give examples of elastomers.

The length of a rod under longitudinal tension $T_1$ is $L_1$ and that under longitudinal tension $T_2$ is $L_2$. What is the actual length of the rod,in the absence of tensions?

The length of an elastic string is $a$ metres when the longitudinal tension is $4 \ N$ and $b$ metres when the longitudinal tension is $5 \ N$. The length of the string in metres when the longitudinal tension is $9 \ N$ is