The time taken by sunlight to cross a $5mm$ thick glass plate $(\mu =3/2)$ is

Q. Determine time taken for the sunlight to pass through a window glass of 5 mm thickness when incident normally. $({\mu }_{glass}=1.5)$

Q. Solve $\sqrt{\frac{2\times (9\times {10}^9)(1.6\times {10}^{-19})\left(47\right)(1.6\times {10}^{-19})}{(1.67\times {10}^{-27})(2.5\times {10}^{-14})}}$

Q. The $H-OH$ bond angle in water is ${105}^o$. The $H-OH$ bond distance being 0.94 $\stackrel{\circ }{\text{A}}$. The dipole moment for the molecule is 1.85 D. Calculate the charge on oxygen atom.
Given: cos ${105}^o$ = $-0.25$

Q.

A wire of ${10}^{-3}c{m}^2$ cross sectional area carries a current of 0.25 A, then current density is

Q. If the velocity of light in vacuum is $3\times {10}^{8}m{s}^{-1}$, the time taken (in nanosecond) to travel through a glass plate of thickness $10cm$ and refractive index $1.5$ is :