In the secondary circuit of a potentiometer a cell of internal resistance 1.5 gives balancing length of 52 cm. To get a balancing length of 40 cm, how much resistance is to be connected across the cell?
A
5Ω
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
6Ω
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
7Ω
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
4Ω
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is A5Ω r=1.5Ω,I1=52cm,I2=40cmrR=I1−I2I2 Resisteance R =rI2(I1−I2)=1.5×40(52−40)=1.5×4012=5Ω