In a laboratory experiment, a student uses a Wheatstone bridge to measure an unknown resistance Rx by balancing it against a known standard resistor Rs of 220 . The bridge is constructed with a 100 cm long wire, and the balance point is found at a distance of 75 cm from one end of the wire. Determine the value of the unknown resistance Rx.
160
170
293.33
20
The Wheatstone bridge experiment is balanced when the ratio of the resistances on one side of the bridge is equal to the ratio of the resistances on the other side. In this case, we have:
Given that Rs = 220 ?, L1 = 75 cm, and L2 = 100 cm, we can solve for Rx:
Solving for Rx:
Therefore, the value of the unknown resistance Rx is approximately 293.33 ?.
Therefore, the correct answer is C.
Study 40% syllabus and score up to 100% marks in JEE