DESIGN EXPERIMENT

Objective:  Design a circuit that will apply the use series resistive method

Problem : Design a series resistive circuit which contains the desired voltage output of 3.7V in a resistor with the given voltage source of 12V.

the first thing we do is we assume resistors for R1 with a given voltage of 3.7V,

then because the the total voltage of each all resistors is 12v because of the battery of 12V we deduct 12v by 3.7V and we an answer 8.7v, this 8.7V is the summation R2 and R3 but we do not know yet the value of resistor of R2 and R3.

by the assumed resistor R1 = 2kΩ

we use voltage divider to find the Rtotal of R2 and R3

Vo=V1 (R1) / R1 + R2

8.7V = 12V ( R2) / 2 + R2

8.7V (2+R2) = 12(r2)

17.4 = 12r2 - 8.7r2

17.4=3.3r2

R23=5.72kΩ
 by using ration and proportion we can find the R3
8.7 / 5.27 = 3.3 / R3
8.7(r3)=3.3(5.27)
R3=2k

R2=Rorig-R3

r2= 5.27-2k
R2=3.27k

this is the equivalent circuit

Reflection:
In order to find the value of each resistor we use voltage divider to get the value of each resistors and also by using the ratio and proportion method. based on our laboratory experiment the value of calculated and measured are not exactly the same because of the tolerance of 5% in the resistors.