What is the ratio of speed of infrared and radio waves in vacuum?
The ratio of speed of gamma-rays and X-rays is :
Mention two uses of IR rays.
What is Ray?
Give two uses of uv rays.
A ray of light is icident on a glass plate of refractive index 1.5. The angle between the reflected and refracted rays is 90^@ . What is the ratio of wavelengtth of reflected t refracted rays ?
What is the angle of incidence of a ray if the reflected ray is at an angle of 90^(@) to the incident ray?
