Wheatstone Bridge Method for Absolute Measurement of Resistances

The Wheatstone bridge method is used for the absolute measurement of resistances. It is based on the principle of balancing the unknown resistance with a known resistance. The method is very accurate and is widely used in industry and research.

Working Principle:

The Wheatstone bridge consists of four resistors, arranged in a diamond shape. The unknown resistance is connected in one of the arms of the bridge, and a battery is connected across the opposite two corners of the diamond. A sensitive galvanometer is connected across the other two corners.

When the galvanometer shows zero deflection, it indicates that the bridge is balanced, and the ratio of the known resistances is equal to the ratio of the unknown resistance. The unknown resistance can be calculated using the formula R_1/R_2 = R_3/R_4, where R_1 and R_2 are the known resistances, and R_3 is the unknown resistance.

Advantages:

- It provides very accurate results.
- It is a simple and easy to use method.
- It is widely used in industry and research.

Disadvantages:

- It requires a known resistance for comparison.
- It is not suitable for measuring low resistances.

Conclusion:

The Wheatstone bridge method is a very accurate and widely used method for the absolute measurement of resistances. It is based on the principle of balancing an unknown resistance with a known resistance, and it provides very accurate results. However, it requires a known resistance for comparison and is not suitable for measuring low resistances.

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wheatstone bridge method is used to find unknown resistance...or v can also say that....The Wheatstone bridge works on the principle of null deflection, i.e. the ratio of their resistances are equal and no current flows through the circuit. Under normal conditions, the bridge is in the unbalanced condition where current flows through the galvanometer.