Assertion (A): Angular momentum of the two dipole system is not conserved.
Reason (R): There is a net torque on the system.
1. Both (A) & (R) are true and the (R) is the correct explanation of the (A)
2. Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
3. (A) is true but (R) is false
4. Both (A) and (R) are false
View Answer
For an isolated system of two dipoles, the torques they exert on each other are internal forces. Internal torques within a system cancel each other out, leading to zero net torque on the system. Therefore, according to the conservation of angular momentum \(\frac{d\vec{L}}{dt} = \vec{\tau}_{ext}\)), if the net external torque is zero, the angular momentum of the system is conserved. Hence, both assertion (A) and reason (R) are false.
Assertion (A): When a dipole is placed in a non- uniform electric field dipole must experience non zero force and torque.
Reason (R): Electric dipole is in stable equilibrium in non uniform electric field.
1. (1) Both (A) & (R) are true and the (R) is the correct explanation of the (A)
2. (2) Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
3. (3) (A) is true but (R) is false
4. (4) Both (A) and (R) are false
View Answer
In a non-uniform field, `\( +q \)` and `\( -q \)` experience different forces, leading to a net force and torque. Thus (A) is true. However, a dipole is generally not in stable equilibrium in a non-uniform field, so (R) is false.