A total resistance of 3 ohms is to be producd by combining an unknown resistor R with a 12 ohm resistor. What is the value of R and how is it connected to the 12 ohm resistor
a) 4.0 ohm parallel
b) 4.0 ohm in series
c) 2.4 ohm in parallel
d) 2.4 in series
e) 9.0 in parallel

My work: A, 1/12 + 1/4= 1/3 or 3 ohm resistance

By using only two resistors, R1 and R2, a student is able to obtain resistance of 3 ohm, 4 ohm, 12 ohm, and 16 ohm using the alone combination. The values of R1 and R2 (in ohms) are:
A) 3,4
b) 2,12
c) 3, 16
d) 4, 12
e) 4, 16

My answer is d 4,12. Since 4 is alone, 12 is alone. in series 12+4=16 and in parallel the value is 3.

thank you

correct.

1. 👍
2. 👎
3. 👁
1. 12*R/(12+R) = 3
3R + 36 = 12R.
9R = 36.
R = 4 Ohms in parallel.

4, and 12 Ohms.

1. 👍
2. 👎
2. THE ANSWER IS B, 4OHMS PARALLEL

1. 👍
2. 👎
3. D,4 ohm, series

1. 👍
2. 👎
4. 4 ohm Parallel is correct.

12+ 1/4 =3ohm
=> 4ohms parallel is correct

1. 👍
2. 👎

## Similar Questions

1. ### physics

A 15.0 Ohms resistor is connected in series to a 120V generator and two 10.0 Ohms resistors that are connected in parallel to each other. -What is the total resistance of the load? -What is the magnitude of the circuit current?

2. ### physics

Resistors R1, R2, and R3 have resistances of 15.0 Ohms, 9.0 Ohms and 8.0 Ohms respectively. R1 and R2 are connected in series, and their combination is in parallel with R3 to form a load across a 6.0-V battery. -What is the total

3. ### physics

if one resistor is removed from a parallel circuit, the total current will 1) decrease b) increase c) remain the same and the current flowing through each of the remaining branches ____________________. removing one resistor makes

4. ### Science

Use Ohm’s Law to determine the resistance in a circuit if the voltage is 12.0 volts and the current is 4.0 amps. A.8.0 ohms B. 48 ohms C.3.0 ohms** D.12 ohms

1. ### science

according to ohms law what is the resistance of a lightbulb if that applied voltage is 21.0 V and the current is 3.0 amps? 24 ohms 7.0 ohms** 18 ohms 3.0 ohms

2. ### Physics EM

An ammeter is connected in series to a battery of voltage V_b and a resistor of unknown resistance R_u The ammeter reads a current I_0. Next, a resistor of unknown resistance R_r is connected in series to the ammeter, and the

3. ### Electro 1

Two resistors Ra= 1.95 ohms and Rb = 0.05 ohms are connected in parallel and take a total of 50A. What is the current trough each resistor.

4. ### Phyics

A resistor has a resistance R, and a battery has an internal resistance r. When the resistor is connected across the battery, ten percent less power is dissipated in R than would be dissipated if the battery had no internal

1. ### physics

when you connect an unknown resistor across the terminals of a 1.50 V AAA battery having a negligible internal resistance, you measure a current of 18.0 mA flowing through it .A)what is the resistance of the resistor. B) if you

2. ### Physics ASAP!!

1. Three resistors are placed in series. They have the following resistances: R1 = 20 ohms, R2 = 20 ohms, R3 = 10 ohms. What current would be moved through this circuit by a 5-V power supply? A. 1.0 A B. 0.10 A C. 25 A D. 250 A 2.

3. ### Physics

The constant resistance of a resistor is 30 ohms, independent of the temperature. The resistor is made up of an aluminium resistor with resistance R1 at 0°C in series with a carbon resistor with resistance R2 at 0°C. Evaluate R1

4. ### physics

A current of 0.2 amps passes through a 3 ohm resistor. The resistor is connected to a 6v battery and an unknown resistor. what is the resistance value of the unknown resistor? R1 = 0.6 v R2 = 5.4 v R2 = 0.2amps 5.4/0.2 = 27 ohms