Home
Class 12
PHYSICS
Assertion: If variation in resistance du...


Assertion: If variation in resistance due to temperature is taken into consideration, then current in the circuit I and power produced across the resistance P both will decrease with time.
Reason: `V=IR` is ohm's law.

A

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

B

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

C

If Assertion is true, but the Reason is false.

D

If Assertion is false but the Reason is true.

Text Solution

Verified by Experts

The correct Answer is:
C
Resistance will increase with temperature on heating. Hence current will decrease.
further `P=V^2/R` or `Pprop1/R`
Resistance in increasing. Hence, power consumed across `R` should decrease.
`V=IR` is just an equation between `PD` across a resistance current passing through it and irt resistance. This not Ohm's law.
Promotional Banner

Topper's Solved these Questions

  • CURRENT ELECTRICITY

    DC PANDEY|Exercise Level 1 Objective|40 Videos

  • CURRENT ELECTRICITY

    DC PANDEY|Exercise OBJECTIVE_TYPE|1 Videos

  • CURRENT ELECTRICITY

    DC PANDEY|Exercise Exercise 23.13|2 Videos

  • COMMUNICATION SYSTEM

    DC PANDEY|Exercise Subjective|11 Videos

  • ELECTROMAGNETIC INDUCTION

    DC PANDEY|Exercise Medical entrances gallery|25 Videos

Similar Questions

Explore conceptually related problems

Assertion: In the part of the circuit shown in figure, maximum power is produced across R . Reason : Power P=V^2/R

Assertion: An inductance and a resistance are connected in series with an AC circuit. In this circuit the current and the potential difference across the resistance lag behind potential difference across the inductance by an angle pi//2 . Reason: In LR circuit voltage leads the current by phase angle which depends on the value of inductance and resistance both.

Assertion: In the following circuit the potential drop across the resistance is zero. Reason: The given resistance has low value.

Assertion : In the following circuit the potential drop across the resistance is zero. Reason : The given resistance has low value.

In the following circuit, 18Omega resistor develops 2J/sec due to current flowing through it. The power developed across 10Omega resistance is

When a 4V battery is connected across an unknown resistor there is a current of 100 mA in the circuit. The value of the resistance of the resistor is:

Assertion :In the circuit shown in figure R is variable. Value of current I is maximum when R=r . Reason: At R=r , maximum power is produced across R.

The e.m.f. of a cell is E volts and internal resistance is r ohm. The resistance in exteral circuit is also r ohm. The p.d across the cell will be

A choke of 0.5 H, a capacitor of 15 mu F and resistance of 100 ohm are connected in series across 200 V, 50 Hz main. Find current in the circuit and power factor of the circuit.