Ratio of powers of a convex and concave lens is $\frac{3}{2}$ and their equivalent focal length (when lenses are kept in constant) is 30 cm . Focal lengths of lenses are

A light ray of wavelength 546 nm is incident on an air-glass interface. If the speed of light in air is $3 \times 10^8 \mathrm{~m} / \mathrm{s}$. Then, wavelength of light ray in glass will be

[Take, refractive index of glass, $\mu=1.5$ ]

The focal length of thin convex lens for red and blue rays are $$100 \mathrm{~cm}$$ and $$98.01 \mathrm{~cm}$$, respectively. There, the dispersive power of the material of the lens is

If an object of height $$6 \mathrm{~cm}$$ is viewed through a liquid of refractive index $$\frac{4}{3}$$ vertically at a depth of $$10 \mathrm{~cm}$$. Then what will be its apparent height and apparent distance from the surface of liquid.