The angle of incidence of light is equal to the angle of reflection from the surface. Moreover, the angle of incidence refers to the angle formed by a ray of light and perpendicular to the surface from which the ray is reflected. Accordingly, if the reflection angle is 20 °, then the angle between the horizontal surface and the incident beam will be equal to:
90 ° – 20 ° = 70 °
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.