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# semiconductors watch

1. How does the low number density in semiconductors cause the electrons to travel faster than they do in conductors?
2. Huh? Can you re-phrase the question now you are sober please? lol.

This question can be answered on many different levels. Is this pitched at GCSE, A-level or undergraduate?

I'm assuming you are referring to the charge mobility (drift velocity) of the majority charge carriers in a semiconductor, the relationship between Fermi-level and conduction bands and hence doping atom concentrations?

Give us an idea of which level you want your answer to be and where your problems in understanding are.
3. (Original post by tazmaniac97)
How does the low number density in semiconductors cause the electrons to travel faster than they do in conductors?
Current is charge per second.
For the same current, if you have fewer available charge carriers they need to move faster.
Imagine you have been asked to carry 5 items across a bridge in 1 minute and you can only carry one item...
If it's only you, you need to get across the bridge 5 times in one minute.
If there are 5 carriers available then you only need to get them all across the bridge in one minute. They can take their time. You need to rush!
4. (Original post by uberteknik)
Huh? Can you re-phrase the question now you are sober please? lol.

This question can be answered on many different levels. Is this pitched at GCSE, A-level or undergraduate?

I'm assuming you are referring to the charge mobility (drift velocity) of the majority charge carriers in a semiconductor, the relationship between Fermi-level and conduction bands and hence doping atom concentrations?

Give us an idea of which level you want your answer to be and where your problems in understanding are.
What do you mean by sober? I'm always sober

(Original post by Stonebridge)
Current is charge per second.
For the same current, if you have fewer available charge carriers they need to move faster.
Imagine you have been asked to carry 5 items across a bridge in 1 minute and you can only carry one item...
If it's only you, you need to get across the bridge 5 times in one minute.
If there are 5 carriers available then you only need to get them all across the bridge in one minute. They can take their time. You need to rush!
Thank you so much!

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