What does the arrow drawn on a ray of light indicate?

An outline sketch of a tree is shown in the diagram below. Study the same and answer the question that follo: What does the direction of arrows in B and C indicate?

What does Psi^2 indicate?

What is lateral displacement ? Draw a ray diagram showing the lateral displacement of a ray of light when it passes through a parallel sides glass slab.

Given alongside is a diagrammatic sketch of a part in human lungs (i) Name the parts numbered 1-4 (ii) What do the arrows 5 and 6 indicate ?

Draw a circuit diagram for a bulb connected to a cell with a switch. Mark arrows in the diagram to indicate the direction of flow of current.

In geometrical optics a ray of light is defined as

A ray of light passes from water to air, How does the speed of light change ?

A ray of light falls on a glass plate of refractive index mu=1.5 . What is the angle of incidence of the ray if the angle between the reflected and refracted rays is 90^@ ?

A ray of light falls on a glass plate of refractive index mu=1.5 . What is the angle of incidence of the ray if the angle between the reflected and refracted rays is 90^@ ?

a light ray is incident normally on a plane mirror. a. What is its angle of incidence? b. What is the direction of reflected ray? Show it on a diagram.