λ=Wavelength = .129 m = 0.129 m
E = energy = ?
h =Planck constant = 6.63 × 10^-34 J.s
f = frequency of photo/ electromagnetic radiation = c/λ
c = Speed of light in a vacuum = 3 × 10^8 m/s
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[tex]E = hf \\ \\ E = h \frac{c}{λ} \\ \\ E = 6.63 \times {10}^{ - 34} \frac{3 \times {10}^{8} }{0.129} \\ \\ E = \frac{6.63 \times {10}^{ - 34} \times 3 \times {10}^{8} }{0.129} \\ \\ E = \frac{663 \times {10}^{ - 36} \times 3 \times {10}^{8} }{129 \times {10}^{ - 3} } \\ \\E = \frac{1989 \times {10}^{ - 28} }{129 \times {10}^{ - 3} } \\ \\ E = 15.4 \times {10}^{ - 25} J \\ \\ E = 1.54 \times {10}^{ - 24} J[/tex]
I hope I helped you^_^
