Page 235 - Understanding Automotive Electronics

2735 | CH 6 Page 222 Tuesday, March 10, 1998 1:10 PM

6 SENSORS AND ACTUATORS

8. A thermistor is 12. The resistance of a thermistor
a. a semiconductor temperature a. varies inversely with
sensor temperature
b. a device for regulating engine b. varies directly with
temperature temperature
c. a temperature control system c. is always 100,000 ohms
for the passenger d. none of the above
d. a new type of transistor
13. Duty cycle in a fuel injector
9. Piezoresistivity is actuator refers to the ratio of
a. a property of certain a. fuel on time to fuel off time
semiconductors in which b. fuel off time to fuel on time
resistivity varies with strain c. fuel on time to fuel on time
b. a resistance property of plus fuel off time
insulators d. none of the above
c. metal bonding pads 14. An EGO sensor is
d. an Italian resistor
a. a perfectly linear sensor
10. Reluctance is b. a sensor having two different
a. the reciprocal of permeability output levels depending on
b. a property of a magnetic air/fuel ratio
circuit that is analogous to c. unaffected by exhaust oxygen
resistance in an electrical levels
circuit d. unaffected by temperature
c. a line of constant magnetic 15. A potentiometer is
flux a. a variable-resistance circuit
d. none of the above
component
11. An optical crankshaft position b. sometimes used to sense air
sensor flow
a. senses crankshaft angular c. usable in a throttle angle
position sensor
b. operates by alternately passing d. all of the above
or stopping a beam of light
from a source to an optical
detector
c. operates in a pulsed mode
d. all of the above

222 UNDERSTANDING AUTOMOTIVE ELECTRONICS