Assertion (A) In a meter bridge experiment, null point for an unknown resistance is put inside an enclosure maintained at a higher temperature. The null point can be obtained at the same point as before by decreasing the value of the standard resistance. Reason (R) Resistance of metal increases with increase in temperature.

Question

Assertion (A) In a meter bridge experiment, null point for an unknown resistance is put inside an enclosure maintained at a higher temperature. The null point can be obtained at the same point as before by decreasing the value of the standard resistance. Reason (R) Resistance of metal increases with increase in temperature. (A) If both Assertion and Reason are true and Reason is correct explanation of Assertion. (B) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion. (C) If Assertion is true but Reason is false. (D) If both Assertion and Reason are false.

Tardigrade Admin · Accepted Answer

As there is an increase in temperature, then the value of unknown resistance will increase.
In balanced condition, (referred Wheatstone bridge)

\frac{R}{X} = \frac{l _{1}}{l _{2}}

where,

R =

standard (known resistance)

X =

unknown resistance.

If both Assertion and Reason are true and Reason is correct explanation of Assertion.

If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.

If Assertion is true but Reason is false.

If both Assertion and Reason are false.

As there is an increase in temperature, then the value of unknown resistance will increase. In balanced condition, (referred Wheatstone bridge) XR​=l2​l1​​ where, R= standard (known resistance) X= unknown resistance.

As there is an increase in temperature, then the value of unknown resistance will increase.
In balanced condition, (referred Wheatstone bridge)
$\frac{R}{X} = \frac{l _{1}}{l _{2}}$
where, $R =$ standard (known resistance)
$X =$ unknown resistance.