Question

Night visin cameras are sensitive to energies around 2.21 x 10-19 J. What wavelength of electromagnetic radiation do they use?

Answer 1

Look at the explanation this one is hard

Step-by-step explanation:

show your work:

E = hc/ λ

E λ = hc

λ = hc/E

λ = 6.626 x 10^-34 x 3 x 10^8 / 2.21 x 10^-19

=

8.994 x 10-7 m or 899.4 nm

800nm – 3mm is the range of wavelengths for infrared waves.

Night vision cameras use infrared waves.

Answer 2

8.99×10^-7m

Step-by-step explanation:

The wavelength can be calculated using the expression below

E=hcλ

Where E= energy= 2.21 x 10^-19 J.

C= speed of light= 3x10^8 m/s

h= planks constant= 6.626 × 10^-34 m2 kg / s

E=hcλ

λ= E/(hc)

Substitute for the values

λ=( 2.21 x 10^-19 )/(6.626 × 10^-34 × 3x10^8 )

= 8.99×10^-7m