Question

if R is the resistance of each side and that of galvanometer of a balanced wheatstone bridge, then total resistance across the terminal connecting the battery is :
(i)R

(ii) 2R

(iii) R/2

(iv) R/4

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Answer 1

Answer:

question is wrong

but I don't know answer

Answer 2

Total resistance across the terminal of the battery is R (option- i).

Given: The resistance of each side of  a wheat stone bridge = R

To Find: Total resistance across the terminal of the battery, R₀.

Solution:

To calculate R₀, the formula used:

• In a Wheatstone bridge, in both the lower and the upper branch, two resistance are in series respectively.
• The middle arm's resistance is considered zero.
• The resultants of the two arms i.e. 2R are in parallel to each other.
• And, in parallel connection, the resultant resistance is calculated as-
•        
• 1 / R  = 1 / R₁ + 1/ R₂ + 1 /R₃............+ 1/ Rₙ

Applying the above formula:

1 /  R₀   =  1 / 2R + 1 / 2R

           = 2 / 2R

           = 1 / R

1 /  R₀   = 1 / R

Taking reciprocal on both the side:

R₀  =  R

Hence, the total resistance across the terminal of the battery is R (option-i).