What is Ray ?

What is a ray light ?

What is an electromagnetic spectrum? Arrange the given electromagnetic radiations in the decreasing order of their frequencies. Infrared rays, X-rays, UV rays, gamma rays.

What is a wavefront ? State its relation with ray of light.

What a ray of light passes from air into glass, is the angle of refraction greater than or less than the angle of incidence?

Name the constituent of cathode rays. What is the magnitude of charge and mass present on it?

What is the angle of incidence of a ray if the reflected ray is at an angle of 90^(@) to the incident ray?