Two slits in Young's double slit experiment are $$1.5 \mathrm{~mm}$$ apart and the screen is placed at a distance of $$1 \mathrm{~m}$$ from the slits. If the wavelength of light used is $$600 \times 10^{-9} \mathrm{~m}$$ then the fringe separation is
Water is used as a coolant in a nuclear reactor because of its
The pitch of an error free screw gauge is $$1 \mathrm{~mm}$$ and there are 100 divisions on the circular scale. While measuring the diameter of a thick wire, the pitch scale reads $$1 \mathrm{~mm}$$ and $$63^{\text {rd }}$$ division on the circular scale coincides with the reference line. The diameter of the wire is:
Let us consider two solenoids $$A$$ and $$B$$, made from same magnetic material of relative permeability $$\mu_r$$ and equal area of cross-section. Length of $$A$$ is twice that of $$B$$ and the number of turns per unit length in $$A$$ is half that of $$B$$. The ratio of self inductances of the two solenoids, $$L_A: L_B$$ is