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प्रश्न
Write the principle of working of a metre bridge
उत्तर
Metre bridge follows the principle of Wheatstone bridge. Wheatstone bridge principle states that if four resistance P, Q, R and S are arranged to form a bridge as shown below with a cell ε and one way K between the points A and C and a galvanometer G between the points B and D, then on closing K, if galvanometer shows no deflection, the bridge is balanced.
Then, `P/Q=R/S`
P = resistance of the length l cm of the wire AD = lr
and Q = resistance of the length (100 - l) cm of the wire DC = (100 - l) × r.
where, r is the resistance per unit length of the wire.
संबंधित प्रश्न
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In a meter bridge shown in the figure, the balance point is found to be 40 cm from end A. If a resistance of 10 Ω is connected in series with R, balance point is obtained 60 cm from A. Calculate the values of R and S.
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(b) Determine the balance point of the bridge above if X and Y are interchanged.
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2) the value of the unknown emf e.
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