With the help of potentiometer, we can determine the value of emf of a given cell. The sensitivity of the potentiometer is
(A) directly proportional to the length of the potentiometer wire
(B) directly proportional to the potential gradient of the wire
(C) inversely proportional to the potential gradient of the wire
(D) inversely proportional to the length of the potentiometer wire
Choose the correct option for the above statements :
Solution
<p>A potentiometer is an electrical instrument used to measure the electromotive force (EMF) of a cell.</p>
<p>The sensitivity of a potentiometer is defined as the change in potential difference per unit length of the wire.</p>
<p>It is directly proportional to the length of the potentiometer wire (Option A), because a longer wire has a larger potential difference that can be measured.</p>
<p>It is inversely proportional to the potential gradient of the wire (Option C), because a smaller potential gradient results in a smaller change in potential difference per unit length.</p>
<p>Therefore, the correct answer is (C) A and C only.</p>
About this question
Subject: Physics · Chapter: Current Electricity · Topic: EMF and Internal Resistance
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