Resistors In Series and Parallel Circuits - Keeping It Simple!
⚫ Series Connection
What is Series Connection?
Series connection is one of the basic ways to connect circuit elements. This connection method connects circuit elements (such as resistors, capacitors, inductors, electrical appliances, etc.) one by one end to end. The circuit formed by connecting various electrical appliances in series is called a series circuit. In the series circuit, the currents passing through the electrical appliances are all equal.
Characteristics
①Current: I=I1=I2 (the currents in all parts of the series circuit are equal)
②Voltage: U=U1+U2 (the total voltage in the series circuit is equal to the sum of the voltages of each part of the circuit)
③Resistance: R=R1+R2 (the total resistance in the series circuit is equal to the sum of the series resistances); if n equal-value resistors (R) are connected in series, then Rt=nR
Note: The total resistance is greater than any one of the sub-resistances, because the series resistance is equivalent to increasing the length of the conductor.
④Voltage divider function: U1/U2=R1/R2 (the larger the resistance, the less current will be divided, and vice versa.)
⑤Proportional relationship: current: I1:I2=1:1
Circuit Diagram and Derivation Formula
According to Ohm's law:
⚫ Parallel Connection
What is Parallel Connection?
Parallel connection is another connection method between components, which is characterized by connecting the heads of two components of the same or different types, and the tails of them. Usually used to refer to the connection mode of the electronic components in the circuit, that is, the parallel circuit.
Characteristics
①Current: I=I1+I2 (the current of the main circuit is equal to the sum of the current of each branch)
②Voltage: U=U1=U2 (the voltage of the main circuit is equal to the voltage of each branch)
③Resistance: 1/R=1/R1+1/R2 (the inverse of the total resistance is equal to the sum of the inverse of the resistance of each branch)
Note: The total resistance is smaller than any one of the sub-resistances. The reason is that the parallel connection of resistances is equivalent to increasing the cross-sectional area of the conductor.
Variant: R=R1R2/(R1+R2) This variant is only applicable to the situation where two resistors are connected in parallel, and it is not applicable if two resistors are connected in parallel.
If n equal value (R) resistors are connected in parallel, then Rt=R/n
④Shunting function: I1/I2=R2/R1 (the larger the resistance, the less current will be distributed, and vice versa.)
⑤Proportional relationship: Voltage: U1:U2=1:1
Circuit Diagram and Derivation Formula
The reciprocal of the total resistance of the parallel circuit is equal to the sum of the reciprocals of the resistances in the parallel.
⚫ Frequently asked questions
1. How do you calculate resistors in series and parallel?
To calculate the total overall resistance of a number of resistors connected in this way you add up the individual resistances. This is done using the following formula: Rtotal = R1 + R2 +R3 and so on.
2. What is series and parallel resistance?
In a series circuit, the output current of the first resistor flows into the input of the second resistor; therefore, the current is the same in each resistor. In a parallel circuit, all of the resistor leads on one side of the resistors are connected together and all the leads on the other side are connected together.
3. What is the resistance of two resistors in parallel?
If the two resistances or impedances in parallel are equal and of the same value, then the total or equivalent resistance, RT is equal to half the value of one resistor. That is equal to R/2 and for three equal resistors in parallel, R/3, etc.
4. Why is equivalent resistance less in parallel?
When resistors are connected in parallel, more current flows from the source than would flow for any of them individually, so the total resistance is lower. Each resistor in parallel has the same full voltage of the source applied to it, but divide the total current amongst them.
5. Is resistance higher in series or parallel?
In series circuit, the effective resistance is equal to sum of the resistances of individual components. So total resistance will be on higher side. In parallel circuit, reciprocal of effective resistance is equal to sum of reciprocals of individual resitances. So effective resistance is less.
6. What is the equivalent resistance in series?
In a series circuit, the equivalent resistance is the algebraic sum of the resistances. The current through the circuit can be found from Ohm's law and is equal to the voltage divided by the equivalent resistance. The potential drop across each resistor can be found using Ohm's law.
7. What is maximum effective resistance?
Maximum effective resistance will be when all the resistors are in series combination. So, Reffmax=n R. Minimum effective resistance will be when all the resistors are in parallel combination.
8. Why current is constant in series?
The amount of current in a series circuit is the same through any component in the circuit. This is because there is only one path for current flow in a series circuit.
9. What happens to resistors in parallel?
When resistors are connected in parallel, the supply current is equal to the sum of the currents through each resistor. The currents in the branches of a parallel circuit add up to the supply current. When resistors are connected in parallel, they have the same potential difference across them.
10. What is the difference between equivalent resistance and effective resistance?
Effective resistance is another name given to the impedance. Impedance is a property, which changes with the frequency of the signal. Equivalent resistance is defined to a set of resistors or components having resistance only. The effective resistance can be defined to each component of a circuit.
11. What is resistance and its formula?
The electrical resistance of a circuit component or device is defined as the ratio of the voltage applied to the electric current which flows through it: If the resistance is constant over a considerable range of voltage, then Ohm's law, I = V/R, can be used to predict the behavior of the material.
12. How do you calculate equivalent resistance?
The equivalent resistance of a 4-Ω and 12-Ω resistor placed in parallel can be determined using the usual formula for equivalent resistance of parallel branches: 1 / Req = 1 / R1 + 1 / R2 + 1 / R3
13. How do I measure resistance?
Resistance is measured in ohms; 1 ohm is equal to 1 volt of electrical difference per 1 ampere of current (1 volt/1 amp). You'll find your volt of electrical difference by taking several readings using your equipment. Resistance can be measured with an analog or digital multimeter or ohmmeter.
14. What is called resistance?
Resistance is a measure of the opposition to current flow in an electrical circuit. Resistance is measured in ohms, symbolized by the Greek letter omega (Ω). Ohms are named after Georg Simon Ohm (1784-1854), a German physicist who studied the relationship between voltage, current and resistance.
15.How many ohms is an open circuit?
For an open circuit, the electric resistance is infinity because no current is passing through the circuit. normally, R=V/I, where I=0A that leads the resistance became much higher which is equal to infinity. For short circuit, the resistance equals to zero ohms.
16.What happens if resistance is too high?
If resistance is too high, current will be low if voltage is okay.
NOTE: When the voltage stays the same, such as in an Automotive Circuit... current goes up as resistance goes down, and current goes down as resistance goes up. Bypassed devices reduce resistance, causing high current.
17. Does higher resistance mean more heat?
When current flows through a conductor, heat energy is generated in the conductor. The heating effect of an electric current depends on three factors:
(1) The resistance, R of the conductor. A higher resistance produces more heat.
(2) The time, t for which current flows. The longer the time the larger the amount of heat produced
(3) The amount of current, I. the higher the current the larger the amount of heat generated.
18.What is the maximum resistance allowed for continuity?
0.5 ohms
Earth Continuity Test is performed by measuring the resistance between the third pin (ground) and outside metal body of the product under test. The maximum acceptable value is generally 0.5 ohms although certain standards may specify 0.1 ohms.
19. How many ohms is a short?
Very low resistance -- about 2 ohms or less -- indicates a short circuit.
20. Does series or parallel give more power?
In general, if the power consumed would depend on the circuit structure. But for a simple case, such as two resistors connected in series versus the same resistors connected in parallel (with identical voltage sources in both), the power dissipated in the parallel combination will be greater.
1 comment
Good job.