Sulfide ores are common for the metals:

$A$ rod is fixed between two points at $20^{\circ}C$. The coefficient of linear expansion of the material of the rod is $1.1 \times 10^{-5} /^{\circ}C$ and Young's modulus is $1.2 \times 10^{11} \, N/m^2$. Find the stress developed in the rod if the temperature of the rod becomes $10^{\circ}C$.

If $a \sin^2 \theta + b \cos^2 \theta = c$,then $\tan^2 \theta$ is equal to

$A$ current-carrying rectangular loop is placed near a straight infinitely long current-carrying wire as shown in the figure. The torque acting on the loop is

In order to calculate the map distance of genes on a chromosome,one must know the

The smallest positive root of the equation $\tan x - x = 0$ lies in the interval: