Suppose ` 10^(-17) J` of light enrgy is needed by the interor of human eue to see an object . The photons fo green light ` * lambda = 55 0 nm)` needed to see to object are :

Options

A. ` 27`
B. ` 28`
C. ` 29`
D. ` 30`

Answer

B

Explanation

`E_(Needed ) = 10^(-17) = n. (hc)/( lambda)`
Where (n) is no. of photons needed fo enrgy ` ( hc)/( lambda) ` to provide enrgy fo ` 10^(-17) J`.