Two groups (A and B) of bean plants of similar size and same leaf area were placed in identical conditions. Group A was exposed to light of wavelength of 400-450 nm and group B to light of wavelength 500-550 nm. Compare the photosynthetic rate of the two groups giving reason.

Two slits are made one millimeter apart and the screen is placed one metre away. When blue-green light of wavelength 500 nm is used, the fringe separation is

In a Young's double slit experiment two slits are separated by 2 mm and the screen is placed one meter away. When a light of wavelength 500 nm is used, the fringe separation will be:

An ultraviolet lamp emits light of wavelength 400 nm at the rate of 400 W. An infrared lamp emits light of wave- length 700 nm, also at the rate of 400 W. (a) Which lamp emits photons at the greater rate and (b) what is that greater rate?

In a double-slit experiment, the two slits are separated by one milimeter and the screen is placed one meter away. The fringe separation for blue green light of wavelength 500 nm is

A thin film having refractive index mu" = 1.5" has air on both sides. It is illuminated by white light falling normally on it. Analysis of the reflected light shows that the wavelengths 450 nm and 540 nm are the only missing wavelengths in the visible portion of the spectrum. Assume that visible range is 400 nm to 780 nm. (a) Find thickness of the film. (b) Which wavelengths are brightest in the interference pattern of the reflected light?

(a) Calculate the momentum of a photon of light of wavelength 500 nm. (b) Find the number of photons emitted per second by a 25 W sourse of monochromatic light of wave length 600 nm. (c) How many photons per second does a one watt bulb emit if its efficiency is 10% and the wavelength of light emitted is 500 nm? (d) Monochromatic light of wavelength 300 nm is incident normally on a surface of area 4 cm^(2) . If the intensity of light is 150 m W//m^(2) , determine the rate at which photons strike the surface.

State two conditions to obtain sustained interference of light. In young's double slit experiment, using light of wavelength 400 nm, interference fringes of width X are obtained. The wavelength of light is increased to 600 nm and the separation between the slits is halved. if one wants the observed fringe width on the screen to be the same in the two cases, find the ratio of the distance between the screen and the plane of the slits in the two arrangements.

Two slits in YDSE are placed 2 millimetre from each other. Interference pattern is observedon a screen placed 2 m from the plane of slits. What is the fringe width for a light of wavelength 400 nm?

Two slits in YDSE are placed 2 millimeter from each other. Interference pattern is observed on a screen placed 2m from the plane of slits. What is the fringe width for a light of wavelength 400 nm ?