LIVE Course for free

Rated by 1 million+ students
Get app now
0 votes
19 views
in Physics by (54.3k points)
closed by
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

1 Answer

0 votes
by (30.0k points)
selected by
 
Best answer
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.

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

Categories

...