
Now $\frac{\mathrm{R}_{2}}{\mathrm{R}_{1}}=\frac{3}{2}=\frac{\ell}{100-\ell} \Rightarrow \ell=60 \mathrm{\,cm}$
shift $=20 \mathrm{\,cm}$
$Y :$ The resistivity of a semiconductor decreases with increases of temperature.
$Z :$ In a conducting solid, the rate of collision between free electrons and ions increases with increase of temperature.
Select the correct statement from the following :

