wave motion

Question 1

progressive waves

Answer 1

a wave in which energy carried from one point to another by means of vibration or oscillations within the waves, without transporting matter.

Question 2

transverse waves

Answer 2

vibrations are perpendicular to transfer of energy of wave

Question 2

longitudinal wave

Answer 2

vibrations are parallel to direction of transfer of energy of wave

Question 3

electromagnetic wave

Answer 3

wave consisting of oscillatign electric and magnetic fields that are perpendicular to each other and to the direction of transfer of energy of wave. Does not require a medium for transmission and can travel through a vacuum at speed of light.

Question 3

mechanical wave

Answer 3

req a medium for its transmission

Question 4

wave speed

Answer 4

speed with which energy is transmitted by a wave.

Question 5

wavelength

Answer 5

minimum dist between any 2 points of the wave with the same phase at the same instant

Question 6

ray

Answer 6

direction in which energy of wave is travelling. rays are perpendicular to wave front.

Question 6

wave front

Answer 6

imaginary line/surface joining points which are at the same state of oscillation

Question 7

phase diff

Answer 7

measure of how much one wave is out of step with another or how much 1 particle in a wave is out of step with another

Question 8

intensity of a wave

Answer 8

power transferred by a wave per unit area

Question 9

when is a wave said to be polarised in a direction

Answer 9

if oscillations in a wave are confined to one direction only, in a plane normal to the direction of transfer of energy of the wave, wave is said to be polarised in that direction

Question 10

only what type of waves can be polarised

Answer 10

transverse waves

Question 11

why is it said that an ideal polariser should transmit 50% of all incident unpolarised light

Answer 11

incident light is random mixture of all states of polarisation, and vertical horrizontal components are on aeverage equal.

Question 12

monochromatic meaning

Answer 12

only one wavelength

Question 13

plane polarised

Answer 13

if oscillations in wave is confined to one direction only, and in a plane normal to transfer of energy OF WAVE, wave is said to be polarised in 1 direction only

Question 14

how to detect whether a beam is plane polarised

Answer 14

rotate a polariod through180 degrees between beam and receiver. if there is an angle where receiver does not detect any laser beam, beam is plane polarised