If one of the resistors in a Wheatstone bridge is replaced with a variable resis
Practice Questions
Q1
If one of the resistors in a Wheatstone bridge is replaced with a variable resistor, what is the effect on the balance condition?
It cannot be balanced
It can be balanced by adjusting the variable resistor
It will always be unbalanced
It will short-circuit the bridge
Questions & Step-by-Step Solutions
If one of the resistors in a Wheatstone bridge is replaced with a variable resistor, what is the effect on the balance condition?
Correct Answer: The balance condition can be achieved by adjusting the variable resistor.
Step 1: Understand what a Wheatstone bridge is. It is a circuit used to measure resistance by balancing two legs of a bridge circuit.
Step 2: Identify the components of the Wheatstone bridge. It has four resistors (R1, R2, R3, R4) and a power source.
Step 3: Know the balance condition. The bridge is balanced when the ratio of the resistances in one leg equals the ratio in the other leg: (R1/R2) = (R3/R4).
Step 4: Replace one of the resistors (let's say R4) with a variable resistor. A variable resistor can change its resistance value.
Step 5: Adjust the variable resistor. By changing its resistance, you can modify the ratio of the resistances in the bridge.
Step 6: Achieve balance. When you adjust the variable resistor to the right value, you can make the bridge balanced again, satisfying the condition (R1/R2) = (R3/R4).
Wheatstone Bridge Balance Condition – The balance condition of a Wheatstone bridge occurs when the ratio of the resistances in one leg equals the ratio in the other leg, allowing for zero voltage across the galvanometer.
Variable Resistor Functionality – A variable resistor can be adjusted to change the resistance in the circuit, which can help achieve the balance condition by fine-tuning the resistance values.
