Wavefronts of Light

Q.

The wavefront of distant source of unknown shape is approximately _________.

Q.

What is wavefront and its types?

Q. The displacement of a body is given by s=1/2gt2 the velocity of the body at any time t is

Q. A wavefront at t= t sec is generated by taking the envelope of secondary wavelets from ___________ points on the wavefront at t=0 sec.

1. few
2. all
3. one
4. none

Q. Why does the position of other bands except bright fringe in the centre, depends on the wavelength in the diffraction??

Q. a boat is heding at an angle 127 from the direction of flow The velocity of boat in water is 5 km /h The velocity of flow of water is 4 km/h The displacement of boat along the flow of water is

Q. If a particle is projected with u = 30i cap + 40j cap.Find the displacement at 6

Q. Shown in the figure, are three waves originating from a point source. Points $A,B,C$ lie on trough while points $D,E,F$ lie on crest of the wave. A wavefront emitting from $O$ may pass through,

1. $\text{Either}A,B,C\text{or}D,E,F$
2. $A,B,F$
3. $\text{Either}A,E,C\text{or}B,D,F$
4. $\text{Either}A,D,E\text{or}B,C,F$

Q. Match the following:
$\begin{array}{cc}\text{I. Planar Wavefronts}& \text{1. Water surface waves}\\ \text{II. Spherical Wavefronts}& \text{2. Waves in 3D produced by a point source}\\ \text{III. Circular Wavefronts}& \text{3. Waves in 3D produced by a point source infinitely far away}\end{array}$

1. I-1, II-2, III-3
2. I-3, II-1, III-2
3. I-2, II-1, III-3
4. I-3, II-2, III-1