[ Home ] [ Up ]

1. When objects are 'charged' they have ------ electricity. (lesson 23a)
2. If an object is uncharged, what can you say about the amounts of positive and negative charges? (23a)
3. What do you call an object that is uncharged? (23a)
4. What is the name of the tiny particles that move through a wire when an electric current flows? (23b)
5. A good conductor has a low r---------. (23b)
6. What happens to a bi-metallic strip when you heat it up? (23b)
7. What are the 3 parts of an electrical system? (23c)
8. In a binary system, what number means a) ON? b) OFF? (23c)
9. What does an LDR detect? (23d)
10. What is a thermistor? (23d)
11. What is an LED? (23e)
12. What component can use a small current to switch on a larger current? (23e)
13. The NOT, AND and OR gates are called ----- gates. (23f)
14. A switch is connected through a NOT gate to a buzzer. How can you turn the buzzer off? (23f)
15. You want your burglar alarm to start if somebody opens a door or steps on a pressure pad. What gate would you use? (23f,g)

ANSWERS

1. Static.
2. They are equal.
3. Neutral.
4. Electrons.
5. Resistance.
6. It bends.
7. Input (sensor), processor, output.
8. a) ON = 1     b) OFF = 0
9. Light.
10. A temperature sensor.
11. A light-emitting diode.
12. A relay.
13. Logic.
14. Turn the switch ON.
15. OR gate.