Draw a diagram to show the shape of a square wave pulse on a string when it gets reflected from (i) fixed boundary and (ii) a free end boundary.

Draw a ray diagram showing the path of rays of light when it enters with oblique incidence (i) from air into water , (ii) from water into air.

The equation of a transverse wave travelling along a string is y(xt)=0.3sin(200x-0.5t) what is the equation of the reflected wave when it is reflected by (i) A rigid boundary? (ii) A free end?

What is the phase difference between the incident wave and the reflected wave in the following ? 1. Wave reflected from rigid boundary. 2. Wave reflected from free boundary.

(a) State Huygen's principle . Using this principle draw a diagram to show how a plane wave front incident at the interface of the media gets refracted when it propagates from a rarer to a denser medium. Hence verify Snell's law of refraction. (b) When monochromatic light travels from a rarer to a denser medium, explain the following, giving reasons- (i) Is the frequency of reflected and refracted light same as the frequency of incident light? (ii) Does the decrease in speed imply a reduction in the energy carried by light wave?

Draw diagrams to show the various modes of vibration in (i) an open pipe and (ii) a closed pipe.

Draw P-V diagrams to show (i) isobaric process and (ii) isochoric process.

Draw a diagram showing the reflection of a light ray from a plane mirror. Label on it the incident ray, the reflected ray, the normal, the angle of incidence i and the angle of reflection r.

(a) What are standing waves or stationary waves ? (b) Show that when a transverse wave travels from a rarer to a denser medium it gets reflected with a phase change of pit . Also prove that wien a transverse wave travels from a denser to rarer medium it gets reflected from the surface separating the two media without any phase change.

In Figure, a ray of light A incident from air suffers partial reflection and refraction at the boundary of water. (a) Complete the diagram showing (i) the reflected ray B and (ii) the refracted ray C. (b) How are the angles of incidence i and refraction r related ?

Draw diagrams to show the refraction of light from (i) air to glass, and (ii) glass to air. In each diagram, label the incident ray, refracted ray, the angle of incidence (i) and the angle of refraction (r).