The Hall effect can be used to do all of the following EXCEPT a. ...

[burton19126]

The Hall effect can be used to do all of the following EXCEPT
  a. measure the density of charge carriers.
  b. measure the sign of charge carriers.
  c. prove that some metals and semiconductors use hole conduction.
  d. generate a steady current perpendicular to the current flowing through a wire.
  e. measure magnetic fields.

Question 2

The electrical resistivity of a semiconductor
 

a. becomes quite large at high temperatures.
  b. becomes quite large at low temperatures.
  c. is fairly independent of temperature.
  d. is much lower than the resistivity of a metal at room temperature.

[Dominic]

Answer to Question 1

b.
The Hall effect can be used to measure the sign of charge carriers by noting the sign on the hall potential difference V_H.

Answer to Question 2

b.
The electrical resistivity grows quite large at low temperatures

[burton19126]

Thanks for the timely response, appreciate it

[Jossy]

Great answer, keep it coming