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The human eye is most sensitive to green...

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 nearly

A

`10^(-6)ms^(-1)`

B

`10^(-8)ms^(-1)`

C

`10^(-10)ms^(-1)`

D

`10^(-13)ms^(-1)`

Text Solution

Verified by Experts

The correct Answer is:
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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