Suppose 10-17 J of energy is needed by the interior of human eye to see an object. How many photons of green light (λ=550 nm ) are needed to generate this minimum amount of energy?

Question

Suppose 10-17 J of energy is needed by the interior of human eye to see an object. How many photons of green light (λ=550 nm ) are needed to generate this minimum amount of energy? (A) 14 (B) 28 (C) 39 (D) 42

Tardigrade Admin · Accepted Answer

Let the number of photons required =n n (h c/λ)=10-17 n=(10-17 × λ/h c) =(10-17 × 550 × 10-9/6.626 × 10-34 × 3 × 108) =27.6=28 photons

Q. Suppose $1 0^{- 17} J$ of energy is needed by the interior of human eye to see an object. How many photons of green light $(λ = 550 nm)$ are needed to generate this minimum amount of energy?

14

28

39

42

Let the number of photons required $= n$

$n \frac{h c}{λ} = 1 0^{- 17}$

$n = \frac{1 0 ^{- 17} \times λ}{h c}$

$= \frac{1 0 ^{- 17} \times 550 \times 1 0 ^{- 9}}{6.626 \times 1 0 ^{- 34} \times 3 \times 1 0 ^{8}}$

$= 27.6 = 28$ photons

Q. Suppose 10−17J of energy is needed by the interior of human eye to see an object. How many photons of green light (λ=550nm) are needed to generate this minimum amount of energy?

14

28

39

42

Let the number of photons required =n nλhc​=10−17 n=hc10−17×λ​ =6.626×10−34×3×10810−17×550×10−9​ =27.6=28 photons

Q. Suppose $1 0^{- 17} J$ of energy is needed by the interior of human eye to see an object. How many photons of green light $(λ = 550 nm)$ are needed to generate this minimum amount of energy?

Let the number of photons required $= n$

$n \frac{h c}{λ} = 1 0^{- 17}$

$n = \frac{1 0 ^{- 17} \times λ}{h c}$

$= \frac{1 0 ^{- 17} \times 550 \times 1 0 ^{- 9}}{6.626 \times 1 0 ^{- 34} \times 3 \times 1 0 ^{8}}$

$= 27.6 = 28$ photons