The resistivity of a metal is a function of temperature because_____________?
A. the amplitude of vibration of the atoms varies with temperature
B. the electron density varies with temperature
C. the electron gas density varies with temperature
A. the amplitude of vibration of the atoms varies with temperature
B. the electron density varies with temperature
C. the electron gas density varies with temperature
A. Speed of the machine
B. Contact pressure
C. Surface conditions of brush and commutator
D. Excessive sparking
E. All of the above
A. Age hardening
B. Alloying
C. Temperature
D. Cold work
E. All of the above
A. less than that of unbounded electron
B. greater than that of unbounded electron
C. equal to that of unbounded electron
D. infinite
E. none of the above
A. adding impurities
B. reducing temperatures
C. application of magnetic field
D. any of the above
A. Kanthal
B. Manganin
C. Nichrome
D. Eureka
A. positive ions only
B. negative ions only
C. positive and negative ions
D. electrons and holes