Question

Photosynthetic Active Radiation $(PAR)$ has the following range of wavelengths

• A. 400 - 700 nm
• B. 450 - 950 nm
• C. 340 - 450 nm
• D. 500 - 600 nm

Answer 1

Answer: (A)

400 - 700 nm

Answer 2

The cosmic rays, $X$-rays, $UV$-rays, the visible spectrum, infra red rays, radio waves, coming from sun are constituted electromagnetic spectrum. The waves of each of these types have a characteristic range of wavelengths. The visible spectrum, which is also known as Photosynthetic Active Radiation $(PAR)$, has a range of wavelength of $380\, nm$ to $760\, nm$. This part of electromagnetic spectrum is responsible for photosynthesis.