- #1
Shivang kohlii
- 19
- 1
Homework Statement
Figure shows a potentiometer circuit for comparison of two resistances , the balance point with standard resistor R = 10 ohm , is found to be 58.3 , while that with unknown resistance X is 68.5 cm , determine the value of X .
b) what might you do if you failed to find the balance point with the given cell end e?
Homework Equations
R/X = L1/L2
K = potential gradient across AB
I1 = current when R is connected
I2 = current when X is connected
3.attempt at a solution
I understand that the potential difference across AP = EF
I.e. k×58.3= I1 × R , where I is the current when R is connected to circuit
And I1×R = E - (2)
Also when X is connected and R is removed ,
k× 68.5 = I2 × X
Also I2 × X = E ... - (1)
But then that means that from 1 and 2 , k × 58.3 = k× 68.5 ? That's obviously wrong!
I don't get it ... I guess somehow I1 × R = E1 and I2× X = E2 with E1 is not equal to E2... If I do that answer comes rightly ...
But shouldn't E1 = E2 as ,
potential difference across EF = potential difference across LM = E always ??
Thank you!
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