Draw a representative diagram of a D.C. motor. Label the armature.

The following diagram is of the simplified version of an electron gun which is an integral part of a cathode ray tube. $\text{'}\mathrm{A}\text{'}$ is a filament and $\text{'}\mathrm{B}\text{'}$ is a metal cylinder.

Copy the diagram in your answer book. Draw a pair of plates ${\mathrm{P}}_1$ and ${\mathrm{P}}_2$ to apply electric field, a screen $\mathrm{S}$ and an enclosure.

The following diagram is of the simplified version of an electron gun which is an integral part of a cathode ray tube. $\text{'}\mathrm{A}\text{'}$ is a filament and $\text{'}\mathrm{B}\text{'}$ is a metal cylinder.

What are the functions of $\mathrm{A},\mathrm{B},{\mathrm{P}}_1$ and ${\mathbf{P}}_{\mathbf{2}}$

${}_{12}{}^{27}\mathrm{Mg}\stackrel{\mathrm{\beta }}{\to }\mathrm{Al}\stackrel{\mathrm{\gamma }}{\to }$

In the above nuclear reaction.

${}_{12}{}^{27}\mathrm{Mg}$ emits a $\beta$- particle and is transformed to aluminium. Write the mass number and the atomic number aluminium.

${}_{12}{}^{27}\mathrm{Mg}\stackrel{\mathrm{\beta }}{\to }\mathrm{Al}\stackrel{\mathrm{\gamma }}{\to }$

In the above nuclear reaction.

Aluminium emits $\gamma$-ray. What is the resulting nucleus?