Question

In which part of the electromagnetic spectrum is the wavelength of $4000\dot{A}$ situated ?

• A. in invisible part
• B. in visible part
• C. in ultraviolet part
• D. in infrared part

Answer 1

Answer: (B)

in visible part

Visible light is usually defined as having a wavelength in the range of 400nm to 700 nm between the infrared and the ultraviolet. $4000A=4000\times {10}^{-10}=400nm$ which is in the visible region of electromagnetic spectrum(Violet).