Two groups (A & B) of bean plants 450nm & Group B to light of wave of similar size and same leaf area were length of 500-550nm. Compare the placed in identical conditions. Group A photosynthetic rate of the2 groups givwas exposed to light of wavelength 400 reasons.

In an experiment on photoelectric effect, the stopping potential is measured for monochromatic light beams corresponding to different wavelength. The data collected are as follows: wavelength (nm): 350 400 450 500 550 stopping potential (V): 1.45 1.00 0.66 0.38 0.16 Plot the stopping potential against inverse of wavelength on a graph paper and find (a) the Planck constant, (b) the work function of the emitter and (c) the threshold wavelength .

Two sources S_1 and S_2 emitting light of wave length 600 nm are placed a distance 1.0x10^-2 cm apart. A detector can be moved on the litre line S_1P which is perpendicular to S_1S_2 . a.What would be the minimum and maximum path differrence at the detector as it is moved alog the line S_1P ? b. Locate the position of the farthest minimum detect.