Question:
Why does an electric bulb become dim when an electric heater in parallel circuit is switched ON?
Why does an electric bulb become dim when an electric heater in parallel circuit is switched ON?
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More appliances ON β More current β Voltage drop β Bulb dims.
Updated On: Feb 27, 2026
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Solution and Explanation
Explanation:
- When a heater is switched ON in parallel, the total current drawn from the source increases.
- Due to internal resistance of the power supply or wiring, the voltage across each appliance may drop slightly.
- As a result, less voltage is available across the bulb.
- Reduced voltage decreases the brightness of the bulb, making it appear dim.
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