The human eye is most sensitive to green light of wavelength 505 nm. Experiments have found tthat when people are kept in a dark room until their eye adapt to the darkness, a single photon of green light will trigger receptor cells in the rods of the retina. The velocity of typical bacterium of mass `9.5xx10^(-12)`g, if it had absorbed all energy of photon ,is nearlyA. `10^(-6)ms^(-1)`B. `10^(-8)ms^(-1)`C. `10^(-10)ms^(-1)`D. `10^(-13)ms^(-1)`

The human eye is most sensitive to green light of wavelength 505 nm. E

1.	The human eye is most sensitive to green light of wavelength 505 nm. Experiments have found tthat when people are kept in a dark room until their eye adapt to the darkness, a single photon of green light will trigger receptor cells in the rods of the retina. The velocity of typical bacterium of mass `9.5xx10^(-12)`g, if it had absorbed all energy of photon ,is nearlyA. `10^(-6)ms^(-1)`B. `10^(-8)ms^(-1)`C. `10^(-10)ms^(-1)`D. `10^(-13)ms^(-1)`
Answer» Correct Answer - D Momentum of photon of green light, `p=(h)/(lamda)=(6.626xx10^(-34))/(505xx10^(-9))1.3xx10^(-27)kgms^(-1)` Velocity of bacterium, `v=(p)/(m)=(1.3xx10^(-27))/(9.5xx10^(-15))` `=1.368xx10^(-13)ms^(-1)`

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