Homework for Diodes Page 1 of 3 Please circle your answer Students Name:___________________________ Date:__________ Please circle your answer Resistors that change with Temperature changes are called: Broken ; b) Thermistors ; c) Variable ; d) sensors The LDR varies its resistance with changes in ________ levels: Light ; b) Water ; c) Sound ; d) Heat Semiconductors are made by adding _______ to Silicon: Water; b) copper ; c) impurities; d) rubber A N-type semiconductor material contains excess _______: Protons; b) electrons; c) Neutrons; d) Atoms Adding impurities to silicon to produce a semiconductor is called ______: Doping; b) Fixing; c) cheating The layer formed at the junction of a diode is called the _______ layer: a) Neutral ; b) common; c) Depletion; d) twilight

Homework for Diodes Page 2 of 3 Please circle your answer Students Name:____________________________ Date:___________ Please circle your answer 7) If a Diode is conducting current it must be: a) Broken ; b) Reverse-Biased ; c) Forward-Biased ; d) reversed 8) The semiconductor material LEDs are made from is: Silicon ; b) old tires ; c) plastic d) Gallium-Arsenide 9) A LED is a special type of Diode: T F 10) LEDs need to be Forwarded-Biased to produce light: T F 11) A LED MUST be used with current-limiting resistor in series; T F 12) When the light on a LDR is increased, the resistance goes up: T F 13) The light output of a LED will Increase with Increasing current: T F 14) A Diode that is Reverse-Biased has a High resistance: T F 15) ‘Holes’ is the term used to indicate the Absence of electrons in a semiconductor material: T F

Homework for Diodes Page 3 of 3 Please circle your answer Students Name:___________________________ Date:__________ Please circle your answer 16) The area of a diode with no net charge is called the _______: Anode ; b) Depletion layer ; c) Cathode ; d) netural zone 17) Diodes Have Zero resistance when they are Forward-Biased: True; b) Sometimes True ; c) False; d) Undetermined 18) If the temperature goes up on a Thermistor, the resistance: Stays the same; b) goes up; c) goes down 19) Large current Diodes produce _________ when forward-biased: Water; b) Smoke; c) Heat; d) noise 20) FSRs change resistance with changes in______: a) Heat; b) Light; c) Strain d) sound