Consider the following statements 1. Clear sky appears blue due to poor scattering of blue wavelength of visible light. 2. Red part of light shows more scattering than blue light in the atmosphere. 3. In the absence of atmosphere, there would be no scattering of light and sky will look black. Which of the statements given above is/are correct ?

Statement 1 is incorrect because the clear sky appears blue due to the strong scattering of shorter blue wavelengths, not poor scattering [1][t1]. According to Rayleigh scattering, the intensity of scattered light is inversely proportional to the fourth power of the wavelength, meaning shorter wavelengths (blue) scatter much more efficiently than longer ones (red) [t1][t9]. Statement 2 is incorrect because red light, having a longer wavelength, shows significantly less scattering than blue light in the atmosphere [c1][t2]. Statement 3 is correct; in the absence of an atmosphere, there are no gas molecules or fine particles to scatter sunlight [c1]. Consequently, light would travel in a straight line without being redirected toward the observer's eyes from different parts of the sky, making the sky appear black or dark, as observed from the moon [t4][t7].

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 10: The Human Eye and the Colourful World > 10.6.2 Why is the colour of the clear Sky Blue? > p. 169