Physics · 2020
JEE Main · 8 January 2020, Shift 1 · Q20
The length of a potentiometer wire is 1200 cm and it carries a current of 60 mA. For a cell of emf 5 V and internal resistance of 20 Ω, the null…
The length of a potentiometer wire is $\displaystyle 1200$ cm and it carries a current of $\displaystyle 60$ mA. For a cell of emf $\displaystyle 5$ V and internal resistance of $\displaystyle 20 \Omega$, the null point on it is found to be at $\displaystyle 1000$ cm. The resistance of whole wire is :
Official answer
(3)
$\displaystyle 100 \Omega$
More from Current Electricity
- Resistances are connected in a meter bridge circuit as shown in the figure. The balancing length l_1 is 40 cm. Now an unknown resistance x is…2022
- A battery of 6 V is connected to the circuit as shown below. The current I drawn from the battery is:2022
- The ratio of the equivalent resistance of the network (shown in figure) between the points a and b when switch is open and switch is closed is x: 8.…2021
- The H amount of thermal energy is developed by a resistor in 10 s when a current of 4 A is passed through it. If the current is increased to 16A, the…2023
- A 4 V battery with internal resistance 1 Ω and a 6 V battery with 2 Ω internal resistance are connected to a resistor of 5 Ω as shown in fig. The…2021
- Two cells are connected between points A and B as shown. Cell 1 has emf of 12 V and internal resistance of 3 Ω. Cell 2 has emf of 6V and internal…2023
- The current density in a cylindrical wire of radius 4 mm is 4 × 10^6 Am^-2. The current through the outer portion of the wire between radial…2022
- For the two cells having same EMF E and internal resistance r, the current passing through the external resistor 6 Ω is same when both the cells are…2026
JEE Main 2020 Physics question, with the answer from NTA’s final answer key. Where our answers come from.