A light filter is a plate of thickness `d` whose absorption coefficient depends on wavelength `lambda` as
`x(lambda) = alpha (1-lambda//lambda_(0))^(2) cm^(-1)`,
where `alpha` and `lambda_(0)` are constants. Find the passband `Delta lambda` of this light filter, that is the band at whose edge the attenuation of light is `eta` times that at the wavelength `lambda_(0)`. The coefficient of reflection from teh surfaces of the light filter is assumed to be the same at all wavelengths.

The refractive index of light in glass varies with its wavelength according to equation mu (lambda) = a+ (b)/(lambda^(2)) where a and b are positive constants. A nearly monochromatic parallel beam of light is incident on a thin convex lens as shown. The wavelength of incident light is lambda_(0) +-Delta lambda where Delta lambda lt lt lambda_(0) . The light gets focused on the principal axis of the lens over a region AB. If the focal length of the lens for a light of wavelength lambda_(0) is f_(0) , find the spread AB.

Let S_(1) be the amount of Rayleigh scattered light of wavelength lambda_(1)and S_(2) that of light of wavelength lambda_(2) from a particle of size a . Which of the following statement is true?

The wavelength of light in vacuum is lambda . The wavelength of light in a medium of refractive index n will be

A beam of light of intensity I_(0) falls normally on a transparent plane-parallel plate of thickness l . The beam contains all the wavelengths in the interval from lambda_(1) to lambda_(2) of equal spectral intensity. Find the intensity of the transmitted beam if in this wavelength interval the absorption coefficient is a linear function of lambda , with exterme values x_(1) and x_(2) . The coefficient of reflection at each surfcae is equal to rho . The secondary reflections are to be neglected.

When a metal is illuminated by light of wavelength lambda , the stopping potential is V_@ and for wavelength 2lambda , it is 3V_@ .Then the threshold wavelength is ?

Let be the maximum kinetic energy of photoelectrons emitted by light of wavelength lambda_(1) and lambda_(2) correspondingto wavelength lambda_(2) . If lambda_(1) = 2lambda_(2) then:

When a photosensitive surface is illuminated with light of wavelength lambda , the stopping potential is V_(0) . But when light of wavelength 2lambda is incident on the same surface, the stopping potential is (V_(0))/(4) . What is the threshold wavelength for the surface ?

If lambda_v, lambda_x and lambda_m represents the wavelength of visible light X-ray and microwave respectively then :