manga 156-195

1. What is an example of a semiconductor device?

Diode



2. Why is silicon used in the manufacture of semiconductors?

a silicon crystal does not have electrons that can move freely so electricity hardly passes through it



3. Discuss the difference using an example of the difference between and N-type and P-type semiconductor.

n types have no holes and negative charge while p have a a whole for valence electrons

in p types the whole becomes the carrier of electricity


4. In your own workd describe what a dioode does and the role of N and P type semiconductors.

diodes are a p type and n type semiconductor combined to make a p n junction,

they attract each other and allow current to flow in only one direction



5. What is rectification?

allowing current to flow in only one direction



6. What causes color in an LED? Give and example of what causes a particular color.

electrons and holes join near the pn junction and vanish the energy that is produced causes color in the led. wavelength controls the color,

white light - phosphor down-conversion1 is most commonly based on a blue or near-ultraviolet emitting die that is combined with a yellow-emitting phosphor,

7. What is the relationship between base current and collector current in a transistor?

electrons in connector are drawn to positive poles where they acmalate while electrons in the emitter the negative and accumulate to the base.



8. What are the advantages of a transistor over a switch?

transistors require no contact so it can be fined tuned and better controlled, less likely to fail