Q 12-01-105JEE MainJEE Main 2022 (28 Jul, Shift 1)Easy
Two electric dipoles of dipole moments $1.2\times10^{-30}$ C m and $2.4\times10^{-30}$ C m are placed in two different uniform electric fields of strengths $5\times10^4\ \text{N C}^{-1}$ and $15\times10^4\ \text{N C}^{-1}$ respectively. The ratio of maximum torque experienced by the electric dipoles will be $\dfrac1x$. The value of $x$ is ______ .
Numerical value type. Enter your answer.
Answer: 6
$\tau_{\max} = pE$:
$$\frac{\tau_1}{\tau_2} = \frac{1.2\times10^{-30}\times5\times10^4}{2.4\times10^{-30}\times15\times10^4} = \frac{6}{36} = \frac16$$
$x = 6$.
Solution by Sreeraj P, M.Sc Physics