Discuss the below:
Q1: (i) What is the angle of incidence of the ray that is just totally internally reflected at the core-cladding interface?
(ii) What is the angle a of this ray to the central axis of the fibre when it emerges from the squared off end?
(iii) How long does a ray travelling down the central axis of the fibre take to travel I km (speed of light in a vacuum = 3.00 x 108 m s.1)
(iv) How long does the ray that is just totally internally reflected take to go along I km of fibre?
Q2:(i)iA simple camera has a convex lens of focal length 50 mm. Draw a ray diagram showing where the image is formed if the object is at 200 mm fromn the lens
(ii) What is distance of the image from the lens?
(iii) What is the biggest object which can be photographed at this distance if the film height is 35 mm
(iv) Where is the image of a very distant object formed?
Q3: (i)What is meant by destructive interference and by constructive Interference?
(ii)Two sources SI and S2 of identical acoustic waves with wavelength 3.0 cm are 15 cm apart as shown in the diagram. Calculate the
distance from each source to point 0 and explain why a microphone would detect a loud sound at this point.
(iii) Calculate also the distances to point P 7.5 cm from 0 and describe what a microphone here would detect
(iv) What would the microphone detect if you continued to move it along the line OP?
