OHM's Law

[Jonathan]

Hi to all,

If someone help me out here. The base of a transistors opens at 0.7 volts.
If I am using 5 volts how do I work out the resistance ? Its been a while
since I did ohms law !!

Many thanks
Jonathan

 

[TurboTroll]

Voltage=Current * Resistance

You need to know two of the three before you can derive the third.
Resistance would equal voltage divided by current, but of course, you need
to know voltage and current. You only give the voltage.

"Jonathan" <jonathan@alarm-engineer.freeserve.co.uk> wrote in message
news:cuvset$t4g$1@titan.btinternet.com...

Hi to all,

If someone help me out here. The base of a transistors opens at 0.7 volts.
If I am using 5 volts how do I work out the resistance ? Its been a while
since I did ohms law !!

Many thanks
Jonathan

 

[CLV3]

"Jonathan" <jonathan@alarm-engineer.freeserve.co.uk> wrote in message
news:cuvset$t4g$1@titan.btinternet.com...

Hi to all,

If someone help me out here. The base of a transistors opens at 0.7 volts.
If I am using 5 volts how do I work out the resistance ? Its been a while
since I did ohms law !!

Many thanks
Jonathan

With the info that you gave us it would be impossible to find the resistance
using Ohm's Law. To find any value in a circuit using Ohm's Law you need two
out of the three (voltage, current, resisitance).

 

[Jonathan]

Many thanks for your reply, I managed to work it out using 400mA.

Thank you
Jonathan

 

[Wouter van Ooijen (www.vo]

Many thanks for your reply, I managed to work it out using 400mA.

For the base current of a transistor??? Are you trying to saturate a
3055 or something like that?


Wouter van Ooijen

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