Advertisements
Advertisements
प्रश्न
Monochromatic light of wavelength 600 nm is incident from the air on a water surface. The refractive index of water is 1.33. Find the
- wavelength,
- frequency and
- speed, of reflected and refracted light.
Advertisements
उत्तर
Given: λ = 600 nm, µ = 1.33
(i) In reflection, the ray will reflect back in the same medium as that of the incident ray.
Hence, wavelength (λ) = 600 nm
(ii) Frequency = υ = `"c"/λ = (3 xx 10^8)/(600 xx 10^-9)`
= 0.5 × 1015 Hz
(iii) Speed = 3 × 108 ms−1
In refraction, the speed and wavelength change while the frequency remains the same.
Hence, speed = ν = `"c"/µ = (3 xx 10^8)/(1.33)`
= 2.26 × 108 ms−1
Wavelength = λ = `ν/υ`
= `(2.26 xx 10^8)/(0.5 xx 10^15)`
= 4.52 × 10−7 m
= 452 nm
Frequency = υ = 0.5 × 1015 Hz
APPEARS IN
संबंधित प्रश्न
Monochromatic light of frequency 6.0 × 1014 Hz is produced by a laser. The power emitted is 2.0 × 10−3 W. Estimate the number of photons emitted per second on an average by the source
Two monochromatic rays of light are incident normally on the face AB of an isosceles right-angled prism ABC. The refractive indices of the glass prism for the two rays '1' and '2' are respectively 1.3 and 1.5. Trace the path of these rays after entering the prism.

Two monochromatic rays of light are incident normally on the face AB of an isosceles right-angled prism ABC. The refractive indices of the glass prism for the two rays '1' and '2' are respectively 1.35 and 1.45. Trace the path of these rays after entering the prism.

When monochromatic light travels from a rarer to a denser medium, explain the following, giving reasons:
(i) Is the frequency of reflected and refracted light same as the frequency of incident light?
(ii) Does the decrease in speed imply a reduction in the energy carried by light wave?
Consider the situation shown in the figure. The two slits S1 and S2 placed symmetrically around the central line are illuminated by a monochromatic light of wavelength λ. The separation between the slits is d. The light transmitted by the slits falls on a screen ∑1placed at a distance D from the slits. The slit S3 is at the central line and the slit S4 is at a distance z from S3. Another screen ∑2 is placed a further distance D away from ∑1.Find the ratio of the maximum to minimum intensity observed on ∑2 if z is equal to

(a) \[z = \frac{\lambda D}{2d}\]
(b) \[\frac{\lambda D}{d}\]
(c) \[\frac{\lambda D}{4d}\]
"Monochromatic light should be used to produce pure spectrum". Comment on this statement.
Find the angle of incidence at which a ray of monochromatic light should be incident on the first surface AB of a regular glass prism ABC so that the emergent ray grazes the adjacent surface AC. (Refractive Index of glass = 1 .56)
Answer the following question.
In the diffraction due to a single slit experiment, the aperture of the slit is 3 mm. If monochromatic light of wavelength 620 nm is incident normally on the slit, calculate the separation between the first order minima and the 3rd order maxima on one side of the screen. The distance between the slit and the screen is 1.5 m.
For constructive interference to take place between two monochromatic light waves of wavelength λ, the path difference should be ______.
Monochromatic light of wavelength 396 nm is incident on the surface of a metal whose work function is 1.125 eV. Calculate:
- the energy of an incident photon in eV.
- the maximum kinetic energy of photoelectrons in eV.
