Question

How many photons are contained in a flash of green light (525 nm) that contains 189 kJ of energy?

Answer 1

Answer: 4.99×10²³ photons

Explanation: The energy of a photon is given as

E= hf

h= Planck constant = 6.626×10^-34Js

f= frequency = c/x

C= speed of light = 3×10^8 m/s

x= wavelength= 525nm= 525×10^-9

E= hc/x

E= 6.626×10^-34 × 3×10^8 m/s /( 525×10^-9)

E= 3.79×10^−19 J/ Photon

E= 3.79×10^−22KJ/Photon

189KJ/3.79×10^−22KJ/photon=

4.99×10²³photons.

Therefore the number of photons is

4.99×10²³photons.

Answer 2

There are 4.99 × 10²³  photons contained in a flash of green light (525 nm) that contains 189 kJ of energy.

First, we will calculate the energy (E) of each photon using the Planck-Einstein's relation.

$E = \frac{h \times c}{\lambda}$

where,

• h: Planck's constant (6.63 × 10⁻³⁴ J.s)

• c: speed of light (3.00 × 10⁸ m/s)

• λ: wavelength of the photon (525 nm = 525 × 10⁻⁹ m)

$E = \frac{h \times c}{\lambda} = \frac{6.63 \times 10^{-34}J.s \times 3.00 \times 10^{8}m/s }{525 \times 10^{-9} m } = 3.79 \times 10^{-19 } J$

Each photon has an energy of 3.79 × 10⁻¹⁹ J. The number of photons that amount to 189 kJ (189 × 10³ J) of energy are:

$189 \times 10^{3} J \times \frac{1photon}{3.79 \times 10^{-19 } J} = 4.99 \times 10^{23} photon$

There are 4.99 × 10²³  photons contained in a flash of green light (525 nm) that contains 189 kJ of energy.

You can learn more about photons here: https://brainly.com/question/23180082