Q. Four resistors and form a Wheatstone bridge as shown in the figure. The bridge is balanced when . If and are interchanged, the bridge balances for . The value of is
Physics Question Image

 2607  221 AP EAMCETAP EAMCET 2019 Report Error

Solution:

According to the question, balanced wheat stone bridge, can be shows as follows
image
First case when,
Now, By balanced wheat stone bridge,

Second case when,

From Eqs. (i) and (ii), we get