A potentiometer wire has length 4 m and resistance 8????.
The resistance that must be connected in series with the
wire and an accumulator of e.m.f. 2V, so as to get a potential
gradient 1 mV per cm on the wire is [2015]
(a) 40 ???? (b) 44 ????
(c) 48 ???? (d) 32 ????
Answers
Explanation:
12th
Physics
Current Electricity
Potentiometer and Problems Based on It
A potentiometer wire has le...
PHYSICS
A potentiometer wire has length 4 m and resistance 8Ω. The resistance that must be connected in series with the wire and an accumulator of e.m.f 2V, so as to get a potential gradient 1 mV per cm on the wire is
October 15, 2019
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Sathish Savani
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VIDEO EXPLANATION
ANSWER
the total resistance after adding resistance R in series with potentiometer wire
=8Ω+RΩ
the current in the circuit will be
i=V/R
eq
=
R+8
2V
the potential drop across potentiometer wire will be iR
potentiometer
=
R+8
2V
×8
the potential gradient along length 4 m is given as
=V
p
otetiometer=
4
R+8
2V
×8
the gradient is given as 1mV/cm=.1V/m
4
R+8
2V
×8
=.1
R=32Ω
solution
Answer:
The correct answer is (d)
