Exams › JEE Main › Physics

Two potentiometers, A and B, are each 100 cm long. Potentiometer A has 4 wires, while potentiometer B has 10 wires. They are used to compare the e.m.f.s of two cells. Which potentiometer will produce the greater balancing length?

1. The balancing length is independent of the total wire length.
2. Both A and B will produce the same balancing length.
3. Potentiometer B
4. Potentiometer A

Correct answer: Potentiometer B

Solution

Potentiometer B, having more wires, allows for a finer division of the potential along its length, which can lead to a greater balancing length when comparing e.m.f.s. This increased number of wires enhances the sensitivity of the measurement, making it more effective in achieving a balance.

Related JEE Main Physics questions

• A physical quantity X is defined as ε0L(ΔV/Δt), where ε0 denotes the permittivity of free space, L is a length, ΔV is a potential difference, and Δt is a time interval. The dimensional formula of X matches that of which of the following?
• A set of n identical resistors is arranged once in a series combination and once in a parallel combination. What is the ratio of the larger equivalent resistance to the smaller equivalent resistance?
• A resistance coil is connected to a battery. In which arrangement will the maximum heat be produced?
• A bulb is rated at 220 V and 100 W. If the applied voltage falls by 2.5% from its rated value, by what percentage of the rated power will the power output decrease?
• An ammeter has a coil resistance of R. To extend its measuring range by a factor of n, the shunt resistance needed should be:
• How does the drift velocity Vd depend on the strength of the applied electric field?

⚔️ Practice JEE Main Physics free + battle 1v1 →