text: # Which of the following bulb will glow more brightly than the others?
  
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  Which of the following bulb will glow more brightly than the others?
  1. A bulb with 220 V supply and resistance of 100 ohm
  2. A bulb with 220 V supply and resistance of 50 ohm
  3. A bulb with 110 V supply and resistance of 100 ohm
  4. A bulb with 110 V supply and resistance of 50 ohm
  
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  Correct Answer - Option 2 : A bulb with 220 V supply and resistance of 50 ohm
  
  CONCEPT:
  
  • Resistance: The opposition of the flow of current in an electrical circuit is called its resistance.
  • Ohm's Law: A law that states that electric current is proportional to voltage and inversely proportional to resistance.
  • Mathematically it is written as,
  
  ⇒ V = IR or I = V/R
  
  where R is the resistance, I is current, and V is the voltage across the conductor.
  
  Power in resistance:
  
  $⇒ P=VI = {V^2\over R}=I^2R$
  
  where I is the current and  V is the voltage.
  
  • If the power of the bulb increases, the bulb will become brighter than before.
  
  EXPLANATION:
  
  • Option 1: V = 220 volt and R = 100 Ω
  
  $⇒ P_1= {V^2\over R}= {220^2\over 100}=484 watt$
  
  • Option 2: V = 220 volt and R = 50 Ω
  
  $⇒ P_2= {V^2\over R}= {220^2\over 50}=968 watt$
  
  • Option 3: V = 110 volt and R = 100 Ω
  
  $⇒ P_3= {V^2\over R}= {110^2\over 100}=121 watt$
  
  • Option 4: V = 110 volt and R = 50 Ω
  
  $⇒ P_4= {V^2\over R}= {110^2\over 50}=242 watt$
  
  • Clearly, the power of the bulb in option 2 is greater than the other.
  • We know that If the power of the bulb increases, the bulb will become brighter than before.
  • So the bulb in option 2 will glow more brightly than the others. Therefore, the correct answer is option 2.