Step 1: Recall the definition of Planck’s constant.
Planck's constant \( h \) appears in the relation \( E = h \nu \), where \( E \) is energy and \( \nu \) is frequency.
Step 2: Use dimensional formulas.
Energy: [ML2T-2]
Frequency: [T-1]
Step 3: Derive the dimensional formula of \( h \).
Since \( h = \frac{E}{\nu} \), we have:
\[ [h] = \frac{[ML^2T^{-2}]}{[T^{-1}]} = [ML^2T^{-1}] \] So the dimensional formula of Planck’s constant is: [ML2T-1]
Step 4: Select the correct option.
The derived dimensional formula [ML2T-1] matches option (3).
A temperature difference can generate e.m.f. in some materials. Let $ S $ be the e.m.f. produced per unit temperature difference between the ends of a wire, $ \sigma $ the electrical conductivity and $ \kappa $ the thermal conductivity of the material of the wire. Taking $ M, L, T, I $ and $ K $ as dimensions of mass, length, time, current and temperature, respectively, the dimensional formula of the quantity $ Z = \frac{S^2 \sigma}{\kappa} $ is:
If \( \vec{u}, \vec{v}, \vec{w} \) are non-coplanar vectors and \( p, q \) are real numbers, then the equality:
\[ [3\vec{u} \quad p\vec{v} \quad p\vec{w}] - [p\vec{v} \quad \vec{w} \quad q\vec{u}] - [2\vec{w} \quad q\vec{v} \quad q\vec{u}] = 0 \]
holds for:
Statement-I: In the interval \( [0, 2\pi] \), the number of common solutions of the equations
\[ 2\sin^2\theta - \cos 2\theta = 0 \]
and
\[ 2\cos^2\theta - 3\sin\theta = 0 \]
is two.
Statement-II: The number of solutions of
\[ 2\cos^2\theta - 3\sin\theta = 0 \]
in \( [0, \pi] \) is two.
If \( A \) and \( B \) are acute angles satisfying
\[ 3\cos^2 A + 2\cos^2 B = 4 \]
and
\[ \frac{3 \sin A}{\sin B} = \frac{2 \cos B}{\cos A}, \]
Then \( A + 2B = \ ? \)