Moodle-1 CSE-2023

N-type semi conductor is made by doping

• Tetravalent atom by pentavalent impurity

• Tetravalent atom by trivalent impurity

• Increasing the temperature of the tetravalent atom 

• Decreasing the temperature

Mobility is defined as

• Drift velocity * electric field

• 1/ drift velocity

• Drift velocity /electric field  

• Electric field/drift velocity  

Find the correct answer

• Resistivity= conductivity    

• Resistivity=1/conductivity

• Resistivity *conductivity= 1

• both b and c

Electrical conductivity of a metal decreases

• With increase in temperature

• With decrease in temperature

• Is independent of temperature  

• None of these is correct

Resistance to current flow is due to

•       Impurity  

• Temperature             

• Both a and b

• None of the above

Unit of resistance is

• Ohm    

• mho         

• Ohm-m       

• Ohm/m

Drift velocity is

• Directly proportional to the electric field

• Inversely proportional to the electric field 

• Proportional to the electron charge 

• Proportional to electron mass

Classical free electron theory was proposed by

• Newton      

• Einstein

• Sommerfield    

• Drude and Lorentz

Choose the correct statement

• Metals are good conductor of heat

• Metals are good conductors of electricity

• Both a and b

• None of the above

Electric field intensity is nothing but

• Work done 

• Conductivity

• Resistance           

• Force