a)in a meter bridge the balance point is found to be at 39.5cm from the end A,when the resistance Y is of 12.5 determine the resistance of X.why are the connection between resistors in a wheat stone or metre bridge made of thick copper strips? b)determine the balance point of the bridge of X and Y is interchanged.plz answer
(a) Balance point from end A, l1 = 39.5 cm
Resistance of the resistor Y = 12.5 Î©
Condition for the balance is given as,
X/Y = (100 - l1 )/ l1
X =[ (100 - 39.5)/39.5] x12.5 = 8.2 Î©
Therefore, the resistance of resistor X is 8.2 Î©.
The connection between resistors in a Wheatstone or metre bridge is made of thick copper strips to minimize the resistance, which is not taken into consideration in the bridge formula.
(b) If X and Y are interchanged, then l1 and 100âl1 get interchanged.
The balance point of the bridge will be 100âl1 from A.
100âl1 = 100 â 39.5 = 60.5 cm
Therefore, the balance point is 60.5 cm from A.
Hope this clarifies your doubt.