Learn

Saturday, 31 October

JEE Main 2024 · PhysicsMultiple choiceSingle correctMediumCalculation

JEE Main 4 April 2024, Shift 1, Physics Q50

Question 50 of 90 in this shift, Physics question 20 of 30, Section A.

To measure the internal resistance of a battery, potentiometer is used. For R=10 ΩR = 10\ \Omega, the balance point is observed at l=500l = 500 cm and for R=1 ΩR = 1\ \Omega the balance point is observed at l=400l = 400 cm. The internal resistance of the battery is approximately :
  1. (1)0.1 Ω0.1\ \Omega
  2. (2)0.2 Ω0.2\ \Omega
  3. (3)0.3 Ω0.3\ \OmegaOfficial answer
  4. (4)0.4 Ω0.4\ \Omega

Official answer

Option 3

NTA final key.

Chapter
Current Electricity
Topic
Potentiometer
Idea tested
Internal Resistance Measurement

Same idea in other shifts

Asked 3× in all
  1. 27 Jun 2022, Shift 1 · Q55A cell, shunted by a 8 Ω8\ \Omega resistance, is balanced across a potentiometer wire of length 3 m. The balancing length is 2 m when the…MediumNumerical value
  2. 30 Jun 2022, Shift 1 · Q56The circuit diagram of potentiometer used to measure the internal resistance of a cell (E) is shown in figure. The key ‘K’ is kept closed…MediumNumerical valueHas a figure

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.