How Do Parallel and Series Circuits Work?
The Difference Between Parallel Circuit And Series Circuit is a key topic in physics for board, JEE, and NEET exams. Understanding how current and voltage behave in these circuits helps students solve questions on electrical systems, circuit design, and applications in real life.
Definition of Parallel Circuit
A parallel circuit is an arrangement where electrical components are connected such that each has its own separate branch across the same voltage source. The voltage across each component remains equal to the source.
In parallel circuits, the total current splits among the branches depending on their resistance, but every component experiences the same voltage. This configuration is widely used in household electrical wiring and distribution systems. For more reading, see Difference Between Series And Parallel Circuits.
Definition of Series Circuit
A series circuit connects electrical components end to end, forming a single path for electric current. All components share the same current throughout the circuit.
In a series circuit, the total voltage from the source divides among the components in proportion to their resistance. Series circuits are common where control over current is needed, as in some lighting systems or electronic circuits. Related concepts are explained in Difference Between Resistance And Resistivity.
Difference Table
| Parallel Circuit | Series Circuit |
|---|---|
| Multiple paths for current flow | Only one path for current flow |
| Same voltage across every component | Voltage divides among components |
| Current splits among branches | Current remains same throughout |
| Total current equals sum of branch currents | Total current is same as branch current |
| Total resistance is less than the smallest branch resistance | Total resistance equals sum of all resistances |
| Failure of one component does not stop current in others | Failure breaks the entire circuit |
| Each device works independently | Devices operate dependently; one affects all |
| Used in wiring for homes and complex circuits | Used in simple lamps and small circuits |
| Brightness of bulbs remains same | Bulb brightness may decrease with more components |
| Branch can have independent switches | Single switch controls the whole circuit |
| Easy to add or remove components | All components must remain connected |
| Common in household electronics | Common in low-cost toys or decorations |
| If one branch opens, others still conduct | If a component fails, circuit ceases |
| Calculating total resistance needs reciprocal method | Total resistance = R₁ + R₂ + ... |
| Power distributes according to branch resistance | Power divides based on resistance values |
| Short circuit in one branch does not affect others | Short circuit affects the entire series path |
| Appliances can be turned on/off separately | All must be on or all off together |
| Widely used in electrical distribution networks | Used where a simple current path is needed |
| Better for safety and maintenance | Maintenance often requires circuit shutdown |
| Applicable to high-current devices | Applicable to low-current, simple devices |
Key Differences
- Parallel circuit has multiple current paths
- Series circuit has a single current path
- Voltage is same across all parallel branches
- Current is same through all series components
- Parallel circuits allow independent device control
- Series circuits break if one component fails
Examples
Wiring multiple bulbs in homes is a parallel circuit example. This arrangement ensures each bulb gets the same voltage and continues to work even if one bulb fails. More details appear in Difference Between Series And Parallel Circuits.
Traditional fairy lights connected end to end form a series circuit. If one bulb burns out, the entire string goes off, demonstrating the dependence within series connection.
Applications
- Parallel circuits in household wiring systems
- Parallel arrangement in power distribution boards
- Series circuits in flashlight battery connections
- Series for safety devices needing complete disconnection
- Parallel for complex electronics requiring independent operation
- Series in simple decorations and low-cost devices
One-Line Summary
In simple words, a parallel circuit allows current through multiple paths with the same voltage across each component, whereas a series circuit forces current through a single path, dividing voltage among components.
FAQs on Understanding the Difference Between Parallel and Series Circuits
1. What is the difference between a series circuit and a parallel circuit?
Series circuits have one path for current, while parallel circuits offer multiple paths for current flow. Key differences include:
- Series circuit: If one component fails, all stop working.
- Parallel circuit: If one component fails, others keep working.
- Voltage: Divided in series; the same across all branches in parallel.
- Current: Same throughout in series; splits in parallel branches.
2. What are the advantages of parallel circuits over series circuits?
Parallel circuits offer several benefits compared to series circuits:
- Each component has its own power supply, so one failure doesn't affect others.
- Voltage remains the same across all devices.
- They are commonly used in home wiring for safety and reliability.
3. In a series circuit, what happens if one component fails?
If any component in a series circuit is disconnected or fails, the entire circuit becomes open and all devices stop working. This is because there is only one path for current.
4. How is current distributed in a parallel circuit?
In a parallel circuit, the total current splits into different branches, and each branch receives current according to its resistance. The main features are:
- Total current is the sum of the currents through each branch.
- Each branch operates independently.
5. Why are household electric circuits wired in parallel, not in series?
Household circuits are wired in parallel so that each appliance receives full voltage and can work independently. If one device fails, others continue to operate, ensuring safety and convenience.
6. What are the applications of series circuits and parallel circuits?
Applications vary:
- Series circuits: Used in Christmas lights, simple torch circuits, and some decorative lighting.
- Parallel circuits: Used in home wiring, electrical outlets, and most practical electrical systems for flexibility and safety.
7. Give two examples each of devices or situations using series and parallel circuits.
Series Circuit Examples:
- Old style Christmas tree lights
- Power switch connected in series with a light bulb
- Household electrical outlets
- Bulbs in a room connected to the same switch
8. How does voltage behave in series and parallel circuits?
In a series circuit, the total voltage is divided among the components. In a parallel circuit, each component gets the full supply voltage. This affects how devices perform in both circuits.
9. Which circuit type is safer for home use: series or parallel?
A parallel circuit is safer and preferred in homes because each device works independently. Overloading in one branch does not affect the entire system, reducing risk of total power failure.
10. Can you explain the key features of a parallel circuit as per the CBSE syllabus?
A parallel circuit has branches, each with its own path for current. Key features include:
- Devices function independently.
- Same voltage across all branches.
- Total current is the sum of currents through each branch.
- Used in homes, schools, and most practical applications.
11. Why does a bulb not glow if one bulb fuses in a series circuit but continues to glow in a parallel circuit?
In a series circuit, the flow of current stops if one bulb fuses, so all bulbs go out. In a parallel circuit, current finds alternate paths, so the remaining bulbs keep glowing.
