in a case of a photosenstive material , state the role of threshold wavelength of incident photon Share with your friends Share 0 Sanjay Singh answered this Dear student Minimum amount of energy required to take the electron out of its surface with zero speed is called work function of the metal. Energy carried by a photon with frequency f is E=hf.Now for photoelectric effect this energy must be greater than or equal to work function of the metal for photoelectric effecthf≥W (W is work function)The minimum frequency of photon to take the electron out is called threshold frequency .IF threshold frequency is f0f0=WhThe wavelength corresponding to threshold frequency is called threshold wavelength ( λ0) λ0=cf0velocity of photon=frequency×wavelengthc=f×λSo if frequency increases than wavelength decreases .For photoelectric effect frequency of photon must be greater than threshold frequency otherwise energy will become less thanwork function and no photoelectric takes plaf≥f0cλ≥f0λ≤cf0λ≤ λ0So for photoelectric effect wavelength of photon must be smaller than or equal to threshold wavelength.Regards 0 View Full Answer
