Which of the following quantities do not change when a resistor connected to a battery is heated due to the current?
A
drift speed
B
resistivity
C
resistance
D
number of free electrons
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D
number of free electrons
d Resistance, resistivity and drift velocity varies with relaxation time which is dependent on temperature.
Number of free electrons in a conductor remains invariant even if its temperature changes.Hence correct option is option $D.$
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