Why does the electrical resistance that the battery senses decrease when two lamps are connected in parallel?
When two lamps are connected in parallel to a battery, the electrical resistance the battery senses is less than the resistance of either lamp. This is due to the property of parallel circuits, where the equivalent resistance is less than the smallest resistance.
Explanation:
Parallel Circuits:
In a parallel circuit, each component has its own separate path to the battery. This allows the current to flow through each component without having to pass through any other component. As a result, the total resistance in a parallel circuit decreases as more components are added.
Equivalent Resistance:
When components are connected in parallel, the equivalent resistance of the circuit is calculated differently compared to components in series. In a parallel circuit, the reciprocal of the total resistance is equal to the sum of the reciprocals of the individual resistances. Mathematically, we calculate it as:
1/Req = 1/R1 + 1/R2 + 1/R3 + ...
Where:
- Req is the equivalent resistance of the parallel circuit
- R1, R2, R3, ... are the individual resistances of each component
Effect on Electrical Resistance:
Because the current can flow through each component independently in a parallel circuit, the overall resistance experienced by the battery is reduced. This is in contrast to a series circuit where the total resistance increases as more components are added.
Application:
Parallel circuits are commonly used in household wiring, Christmas lights, and electronic devices with multiple components. By connecting components in parallel, each component receives the full voltage from the source, ensuring proper functioning and preventing one faulty component from affecting the others.
Understanding how parallel circuits work and their impact on electrical resistance is essential in designing and troubleshooting electrical systems. It allows engineers and electricians to create efficient circuits that deliver the desired level of voltage to each component while optimizing energy usage.
In conclusion, the electrical resistance that the battery senses decreases when two lamps are connected in parallel due to the nature of parallel circuits, which offer lower overall resistance compared to series circuits.