NTA Abhyas JEE Main2020PhysicsExperimental PhysicsPractice
In an experiment on measurements of emf of a cell by a potentiometer, the balancing length for a cell of emf E and internal resistance r is found to be l . Now if another cell of emf E and internal resistance 2 r is connected in parallel to the first cell and balancing length determined, then the balancing length will be-
Options
- Al
- B2   l
- Cl 2
- D2 l 3
Correct answer
A. l
Step-by-step solution
Since potentiometer doesn't draw any current to measure the emf of the cell, the balancing length will remain the same. balancing length = l