Electronic Technology

1. Electronic Technology Chapter 19 Preview CRCT Preparation

2. Chapter 19 CRCT Preparation 1. What happens to the current in the circuit if the manual switch is opened? ACurrent stops in the smaller loop but continues in the larger loop. BCurrent stops in the larger loop but continues in the smaller loop. CCurrent stops in both loops. DThe direction of the current is reversed.

3. Chapter 19 CRCT Preparation 1. What happens to the current in the circuit if the manual switch is opened? ACurrent stops in the smaller loop but continues in the larger loop. BCurrent stops in the larger loop but continues in the smaller loop. C Current stops in both loops. DThe direction of the current is reversed.

4. Chapter 19 CRCT Preparation 2. Quinyana is using the circuit diagram to design a sound amplifier. She replaced the manual switch with a microphone. What other part should she replace? AShe should replace the transistor with a speaker. BShe should replace the transistor with a volume control dial. CShe should replace the motor with a speaker. DShe should replace the motor with a volume control dial.

5. Chapter 19 CRCT Preparation 2. Quinyana is using the circuit diagram to design a sound amplifier. She replaced the manual switch with a microphone. What other part should she replace? AShe should replace the transistor with a speaker. BShe should replace the transistor with a volume control dial. C She should replace the motor with a speaker. DShe should replace the motor with a volume control dial.

6. Chapter 19 CRCT Preparation 3. A company produces electronic components that are used in radios to convert alternating current (AC) to direct current (DC). On one assembly line, machines layer an n-type semi-conductor into a mold. What else should be added to complete the component? Aone n-type semiconductor Bone p-type semiconductor Ctwo p-type semiconductors Done p-type semiconductor and one n-type semiconductor

7. Chapter 19 CRCT Preparation 3. A company produces electronic components that are used in radios to convert alternating current (AC) to direct current (DC). On one assembly line, machines layer an n-type semi-conductor into a mold. What else should be added to complete the component? Aone n-type semiconductor B one p-type semiconductor Ctwo p-type semiconductors Done p-type semiconductor and one n-type semiconductor

8. Chapter 19 CRCT Preparation 4. Which of these devices converts sound energy into electrical energy? Atelephone Bspeaker Cdigital alarm clock Dremote control

9. Chapter 19 CRCT Preparation 4. Which of these devices converts sound energy into electrical energy? A telephone Bspeaker Cdigital alarm clock Dremote control

10. Chapter 19 CRCT Preparation 5. Laptop computers have very thin screens. How might a laptop computer screen produce images? AElectron beams sweep the screen and cause fluorescent materials to glow. BLaser beams shine behind the screen and create patterns of reflected light. CVibrations in thousands of electron tubes transfer energy to wells of colored light. D Charged atoms of gas in wells on the screen transfer energy to fluorescent materials.

11. Chapter 19 CRCT Preparation 5. Laptop computers have very thin screens. How might a laptop computer screen produce images? AElectron beams sweep the screen and cause fluorescent materials to glow. BLaser beams shine behind the screen and create patterns of reflected light. CVibrations in thousands of electron tubes transfer energy to wells of colored light. D Charged atoms of gas in wells on the screen transfer energy to fluorescent materials.

12. Chapter 19 CRCT Preparation 6. Cecily uses a remote control to turn on her DVD player. What kind of hardware is the remote? Aa central processing unit Ban input device Can output device Dan interface card

13. Chapter 19 CRCT Preparation 6. Cecily uses a remote control to turn on her DVD player. What kind of hardware is the remote? Aa central processing unit B an input device Can output device Dan interface card

14. Chapter 19 CRCT Preparation 7. Which element in the table could be used with silicon to make a p-type semiconductor? Aboron Bgermanium Cphosphorus Dselenium

15. Chapter 19 CRCT Preparation 7. Which element in the table could be used with silicon to make a p-type semiconductor? A boron Bgermanium Cphosphorus Dselenium

16. Chapter 19 CRCT Preparation 8. Which of the following works in an analog way? Aa remote control for a television Ba volume control dial on a stereo Ca programmable thermostat Da light switch

17. Chapter 19 CRCT Preparation 8. Which of the following works in an analog way? Aa remote control for a television B a volume control dial on a stereo Ca programmable thermostat Da light switch

18. Chapter 19 CRCT Preparation 9. Why do remote-controlled toy cars contain transistors instead of vacuum tubes? ATransistors change AC to DC, but vacuum tubes do not. BTransistors amplify electric current, but vacuum tubes do not. CTransistors are energy sources, but vacuum tubes are not. DTransistors are small and light, but vacuum tubes are not.

19. Chapter 19 CRCT Preparation 9. Why do remote-controlled toy cars contain transistors instead of vacuum tubes? ATransistors change AC to DC, but vacuum tubes do not. BTransistors amplify electric current, but vacuum tubes do not. CTransistors are energy sources, but vacuum tubes are not. D Transistors are small and light, but vacuum tubes are not.

20. Chapter 19 CRCT Preparation 10. Would a diode containing only two p-type semiconductors conduct an electric current? Explain your answer.

21. Chapter 19 CRCT Preparation 10. Answer - This diode would not conduct an electric current. Full-credit answers should include the following points: • A diode needs a p-type and an n-type semiconductor to create a current. • When layers are joined, extra electrons from the n-type layer flow to plug holes in the p-type layer. An electric current is created when an energy source is connected such that the positive terminal is closest to the p-type semiconductor. • If two p-type semiconductors were joined together, there would be no extra electrons to fill in the holes. Therefore, a diode with only two p-type layers would not conduct more than a very weak electric current.

22. Chapter 19 CRCT Preparation 11. Telephones and radios are similar because they both convert signals into sound waves. Describe two ways in which telephones and radios are different.

23. Chapter 19 CRCT Preparation 11. Answers may include: • In telephones, signals are transmitted by electric current to and from the telephone receiver. In radios, signals are transmitted by modulated radio waves from a radio station to a radio receiver. • Telephones are also different from radios because telephones transmit and receive signals. Most commercial radios just receive signals.