Measurement of Medium Resistance by Wheatstone Bridge Method

TL;DR

The Wheatstone Bridge is a simple circuit used to measure medium resistances between 1 ohm and 100 kilo ohms.

Transcript

hello friends in this video we are going to study the most famous wheat stone bridge which is used for the measurement of medium resistances medium resistances are those resistances which are of the value greater than 1 ohm but less than 100 kilo ohms so those resistances which are between this range 1 ohm 200 kilo ohms they are categorized as medi... Read More

Key Insights

• 🔉 The Wheatstone Bridge is a widely used method for measuring medium resistances.
• 🦾 The bridge circuit consists of four arms, with known and unknown resistances.
• 🌉 Null deflection is crucial in balancing the bridge and calculating the unknown resistance.

Questions & Answers

Q: How does the Wheatstone Bridge method work?

The Wheatstone Bridge works by creating a balanced bridge circuit using known and unknown resistances. By varying the standard resistance, the bridge is balanced, and the unknown resistance can be calculated using the balance equation.

Q: What is the significance of null deflection in the Wheatstone Bridge?

Null deflection indicates that no current is flowing through the galvanometer, which means the bridge is balanced. This allows for the calculation of the unknown resistance using the balance equation.

Q: Can the Wheatstone Bridge measure resistances below 1 ohm or above 100 kilo ohms?

No, the Wheatstone Bridge is primarily used for measuring resistances between 1 ohm and 100 kilo ohms. Resistances below 1 ohm or above 100 kilo ohms are not suitable for measurement using this method.

Q: What factors can cause errors in the measurement using the Wheatstone Bridge?

Errors in Wheatstone Bridge measurements can occur due to limiting errors in the resistances, heating up of the elements, effect of connecting leads, and contact resistance. These factors can affect the accuracy of the measured resistance.

Summary & Key Takeaways

• The Wheatstone Bridge is named after the scientist who discovered it and is used to measure medium resistances.

• The circuit consists of four arms with resistances P, Q, R, and S, with P and Q being known resistances and R being the unknown resistance to be measured.

• The bridge is balanced when the galvanometer shows null deflection, and the unknown resistance can be calculated using the balance equation.