There exists a uniform electric field of 20 $\stackrel{^<!--\; ^\; -->}{i}$ N/C. A dipole moment $|\stackrel{\to <!--\; \to \; -->}{P}|$ = 15 cm is placed at angle 30° with electric field. Torque on dipole is.

Correct Answer: 150 Nm

Step-by-Step Explanation:

To find the torque acting on an electric dipole placed in a uniform electric field, we can use the torque formula for a dipole:

$\tau =PE\sin \left(\theta \right)$

Where:
• $\tau$ is the torque acting on the dipole.
• $P$ is the magnitude of the electric dipole moment, given as 15 C·m (Coulomb-meters, written as "cm" in the problem).
• $E$ is the magnitude of the uniform electric field, which is 20 N/C.
• $\theta$ is the angle between the dipole moment vector and the electric field vector, which is 30°.

Now, let's substitute the given values into the formula:

$\tau =15\times 20\times \sin (30°)$

We know that the value of $\sin (30°)=0.5$ (or $\frac{1}{2}$). Substituting this value, we get:

$\tau =300\times 0.5$

$\tau =150\text{Nm}$

Therefore, the torque acting on the dipole is 150 Nm.