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Lab Report 1_Martin Sanner

Page history last edited by Vivien Tsao 7 years ago

a. What resistance do you need to limit current to 30 mA (if using red LED) or 25 mA (if using yellow or green)? Be sure to state which color LED you are using. This resistance refers to the total resistance in series with the LED.

V=3.15v;     |5v-1.85v     (red)


V=I*R; |/I

R=105 Ohm;

V=2.8v;     |green



R=112 Ohm;


b. Is the resistance from question a) a maximum or minimum resistance? That is, in which direction if you change the resistance (higher or lower) would the LED likely fail.

This resistance is the minimumresistance, if it is either higher or lower, the LED wouldn't fail.

-0.5: ambiguous answer... It is the min. resistance.


c. What is the resistance range of the potentiometer?

The Resistance range of a potentiometer is described by r_poten=sin(r_total)*r_total.

It ranges from 0 Ohm to the full resistance.


a. Does it matter what order the components of your circuit are arranged between power and ground? Why or why not?

Since the LED still works with 5 V, though it is more likely to fail, thus, it does not matter.

✓ hmm... you might want to think about the answer again, though it is true it does not matter.


a. Using this battery, what is the minimum resistance required for use with your LED?







Comments (1)

Vivien Tsao said

at 6:27 pm on Jul 11, 2013

Good job!

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