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to obtain a multimeter reading of 1 v between b and c in the circuit the value of r2 would have to be.

User Joshdcomp
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2 Answers

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6 votes

Answer:

10k

Step-by-step explanation:

User Bigtlb
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Complete question:

In the circuit shown in the figure below (See image attached), suppose that the value of R1 is
500\,k\Omega. To obtain a multimeter reading of 1 V between points B and C in the circuit, the value of R2 would have to be.

Answer:


R2=0.1\Omega

Step-by-step explanation:

First, we are going to the find current trough the circuit, because the resistors are on series the current is the same on each resistor so I=I1=I2. The Ohm's law for the circuit is:


V=R_(T)*I (1) , with V the voltage of the battery (6V), I the current trough the circuit and
R_(T) the total resistance of the circuit, but for resistors on series the total resistance is the sum of the individual resistance so
R_(T) = R1+R2 (2).

Using (2) on (1) and solving for I:


I=(V)/(R1+R2) (3)

Ohm's law is true for the individual resistors too so we're going to apply that on R2:


V2=R2*I2, but remember I2=I


V2=R2*I (4), using (3) on (4)


V2=R2* (V)/(R1+R2), solving for R2:


R1*V2+R2*V2=R2V


R1*V2=R2(V-V2)


R2=(R1V2)/(V-V2)=(500*10^(3)\Omega*1V)/(6V-1V), V2= 1V because we want that reading on the multimeter.


R2=100\,k\Omega

to obtain a multimeter reading of 1 v between b and c in the circuit the value of-example-1
User Kevin Sanchez
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