Science Assertion & Reason

Assertion: Presbyopia is due to ageing of human beings.
Reason: For those persons, ciliary muscles of the eye become weak.

Assertion: Power of a lens is the reciprocal of its focal length.
Reason: The unit of power is one dioptre when the unit of focal length is one metre.

Assertion: Raman scattering the scattering of monochromatic light by atoms and molecule of a liquid.
Reason: The wavelength of Raman lines is same.

Assertion: Light waves travel in straight lines.
Reason: Rectilinear propagation of light confirm the above mentioned properly.

Assertion: If a convex lens is placed in water, its convergence power decrease.
Reason: Focal length of lens is independent of refractive index of the medium.

Assertion: A single lens produces a coloured image of an object illuminated by white light.
Reason: The refractive index of material of lens is different for different wavelength of light.

Assertion: The refractive index of a prism depends only on the material of the prism.
Reason: The refractive index of a prism depends upon the refracting angle and angel of minimum deviation.

Assertion: Raman spectrum of a liquids contains lines whose frequencies are not equal to that of incident radiation.
Reason: If a photon strikes an atom in a liquid that is in existed state photon losses energy.

Assertion: Colours can be scan in thin layers of oil on the surface water. Reason: White light is composed of several colours.

Assertion : The sun looks bigger in size at sunrise and sunset than during day.
Reason : In detraction light rays bend around the edges of the obstacle.