Physics MCQs for NEET — Practice Questions with Answers

Variation of scattering mechanism with temperature

Crystal structure

Variation of the number of charge carriers with temperature

Type of bond

Zero               

Proton

Neutron         

Electron

 ${10}^{17}/{\mathrm{m}}^3$        

${10}^{15}/{\mathrm{m}}^3$

 ${10}^4/{\mathrm{m}}^3$          

${10}^2/{\mathrm{m}}^3$

Copper               

Aluminium

Iron                   

Germanium

The valence band is partially empty and the conduction band is partially filled

The valence band is completely filled and the conduction band is partially filled

The valence band is completely filled

The conduction band is completely empty

There are no free electrons at room temperature

There are no free electrons at 0 K

The number of free electrons increases with rise of temperature

The charge carriers are electrons and holes

The donor level lies closely below the bottom of the conduction band

The donor level lies closely above the top of the valence band

The donor level lies at the halfway mark of the forbidden energy gap

None of above

When we heat a semiconductor its resistance increases

When we heat a semiconductor its resistance decreases

When we cool a semiconductor to 0 K then it becomes super conductor

Resistance of a semiconductor is independent of temperature

Positively charged

Negatively charged

Positively charged or negatively charged depending upon the type of impurity that has been added

Electrically neutral

 ${\mathrm{n}}_{\mathrm{e}}$ increases and ${\mathrm{v}}_{\mathrm{d}}$ decreases

 ${\mathrm{n}}_{\mathrm{e}}$ decreases and ${\mathrm{v}}_{\mathrm{d}}$ increases

Both ${\mathrm{n}}_{\mathrm{e}}$ and ${\mathrm{v}}_{\mathrm{d}}$ increases

Both ${\mathrm{n}}_{\mathrm{e}}$ and ${\mathrm{v}}_{\mathrm{d}}$ decreases