Question

What is the effect of heat on the resistances in a Wheatstone bridge?

(a) no effect

(b) increases the voltage drop across the circuit

(c) decreases the current flowing through the circuit

(d) causes a permanent change in the resistance values

This question was posed to me in exam.

I'm obligated to ask this question of Limitations of Wheatstone Bridge in division Measurement of Resistance of Electrical Measurements

Answer 1

Right choice is (d) causes a permanent change in the resistance values

To explain I would say: As the current flowing through the Wheatstone bridge circuit increases, the temperature of the resistance increases. As a result the resistance values are changed permanently.