The resistivity of germanium and silicon  (increases/decreases) with increase in temperature.

Resistance is the property of a conductor that opposes the flow of charge through it. It is given by $R=\frac{V}{I}$ where $V=$ potential difference across the conductor and $I=$ current through the conductor.

The resistance of conductor depends on the length, area of cross-section and nature of material of the conductor.

It also depends on the temperature of the conductor.

If $\rho$ be the resistivity of the material of the conductor, $l$ be its length and $A$ be its area of cross-section, answer the following question:

Resistance of a conductor in terms of $\rho$, $l$ and $A$ is given by

Resistance is the property of a conductor that opposes the flow of charge through it. It is given by $R=\frac{V}{I}$ where $V=$ potential difference across the conductor and $I=$ current through the conductor.

The resistance of conductor depends on the length, area of cross-section and nature of material of the conductor.

It also depends on the temperature of the conductor.

If $\rho$ be the resistivity of the material of the conductor, $l$ be its length and $A$ be its area of cross-section, answer the following question:

When a potential difference of $12.5 \mathrm{V}$ is applied across the conductor, $0.5 \mathrm{A}$ of current flows through it. Its resistance is