If the resistance of one arm of a Wheatstone bridge is increased, what effect do
Practice Questions
Q1
If the resistance of one arm of a Wheatstone bridge is increased, what effect does it have on the balance condition?
It remains balanced
It becomes unbalanced
It depends on the other resistances
It increases the current
Questions & Step-by-Step Solutions
If the resistance of one arm of a Wheatstone bridge is increased, what effect does it have on the balance condition?
Step 1: Understand what a Wheatstone bridge is. It is a circuit used to measure unknown resistances by balancing two legs of a bridge circuit.
Step 2: Identify the arms of the Wheatstone bridge. There are four resistors in total: R1, R2, R3, and R4.
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: Consider what happens when you increase the resistance of one arm (let's say R1). This changes the ratio of R1 to R2.
Step 5: Realize that increasing R1 makes the left side of the equation (R1/R2) larger, which disrupts the balance.
Step 6: Conclude that when the balance condition is disturbed, the bridge becomes unbalanced.
Wheatstone Bridge Balance Condition – The balance condition of a Wheatstone bridge occurs when the ratio of resistances in one arm equals the ratio in the other arm, allowing for no current to flow through the galvanometer.
Effect of Resistance Change – Changing the resistance in one arm alters the ratio of resistances, which disrupts the balance condition and causes current to flow through the galvanometer.
