Red light has a wavelength of 700 nm and a frequency of 4.3 x 10^14 s^-1. What is the energy of a single photon of red light? A. 2.85 x 10^-20
B. 2.85 x 10^19
C. 2.85 x 10^-34
D. 2.85 x 10^-19

E = 2.85×10⁻¹⁹ J

Explanation:

Given data:

Wavelength of light = 700 nm

Frequency of light = 4.3×10¹⁴ s⁻¹

What is the energy of light = ?

Solution:

Formula:

E = h × f

h = plancks constant = 6.63×10⁻³⁴ Js

by putting values,

E =  6.63×10⁻³⁴ Js × 4.3×10¹⁴ s⁻¹

E = 28.5×10⁻²⁰ J

E = 2.85×10⁻¹⁹ J

passing a magnet thought the

mixture , because iron gets attracted to magnet .

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)