Q. As light travels from a rarer to a denser medium it will have:
Answer: both 2 and 3
Notes: Refraction of light occurs because of change in velocity or speed of light in different media. When ray of light travels from rarer to denser medium, it moves towards the normal. When it travels from denser to rarer medium, it moves away from the normal. When light ray travels from rarer to denser medium, its velocity and wavelength both decrease.