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Assume that 2 xx 10^(-17) J of light ene...

Assume that `2 xx 10^(-17)` J of light energy is needed by the interior of the human eye to see an object. The number of photons of yellow light with `lambda = 595.2`nm are needed to generate this minimum energy is 12x. Then the value of x is _________ .

Text Solution

Verified by Experts

The correct Answer is:
5
`E = n(hc)/(lambda)`
`implies (2xx 10^(-17))/(1.6 xx 10^(-19)) eV = n xx (1240)/(595.2) xx (eV. Nm)/(nm)`
`implies n = 60 implies 12 x = 60 implies x = 5`
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