Oscillations and waves

Question 1

Amplitude

Answer 1

Maximum displacement from the equilibrium point

Question 2

Displacement for waves

Answer 2

distance a particle moves in a particular direction from its mean/ equilibrium position

Question 3

frequency (f)

Answer 3

number of oscillations per unit time

Question 4

Period (T)

Answer 4

time taken for one oscillation

Question 5

Phase difference

Answer 5

Difference in phase between two points

Question 6

Simple harmonic motion

Answer 6

Motion that takes place when the acceleration of an object is proportional to its displacement from its equilibrium point and is directed towards the equilibrium position

Question 7

Transverse wave

Answer 7

Wave in which the direction of motion of the energy transfer is perpendicular to the direction of motion of the particles.

Question 8

Longitudinal waves

Answer 8

Wave in which direction of energy transfer is parallel to the direction of motion of the particles

Question 9

wavefront

Answer 9

Collection of neighboring points on a wave that are in phase

Question 10

Crest

Answer 10

top of a transverse wave

Question 11

trough

Answer 11

bottom of a transverse wave

Question 12

compression

Answer 12

area of high pressure in longitudinal wave

Question 13

rarefaction

Answer 13

area of low pressure in longitudinal wave

Question 14

wavelength

Answer 14

distance between two points in phase with one another

Question 15

Intensity (I)

Answer 15

power per unit area

Question 16

Law of reflection

Answer 16

Angle of incidence= angle of reflection

Question 17

Snell’s law

Answer 17

The ratio of the sine of the angle of incidence and reflection is a constant

Question 18

Refractive index (n)

Answer 18

Ratio of the speed of the wave in the refracted medium to the speed incident on the medium.

Question 19

Diffraction

Answer 19

The bending of a wave around an obstacle or the spreading of a wave through an opening

Question 20

Principle of superposition

Answer 20

When two waves meet, the resultant displacement is the sum of their displacements

Question 21

constructive interference

Answer 21

superposition of two waves that are in phase

Question 22

destructive interference

Answer 22

superposition of two waves that are out of phase

Question 23

path difference

Answer 23

difference in the distances two waves must travel from their sources to a given point

Question 24

standing wave

Answer 24

resultant wave when two waves of equal amplitude and frequency in opposite direction in the same medium meet

Question 25

Node

Answer 25

Locations of constant destructive interference

Question 26

antinode

Answer 26

locations of constructive interference

Question 27

First harmonic

Answer 27

lowest frequency mode of vibration of a standing wave

Question 28

doppler effect

Answer 28

The change of frequency of a wave due to the movement of the source or observer

Question 29

resolution

Answer 29

ability to distinguish between two sources of light

Question 30

rayleigh criterion

Answer 30

when the central maximum of one diffraction pattern overlaps the first maximum of a second diffraction pattern, the two sources are resolved

Question 31

Polarized light

Answer 31

light in which the electric field moves in one plane due to a polarizer

Question 32

polarizer

Answer 32

device that produces plane-polarized light

Question 33

analyzer

Answer 33

polarizer used to detect polarized light

Question 34

Malus’ law

Answer 34

the transmitted intensity of polarized light is equal to the product of the incident intensity times square of the cosine of the angle between the analyzer and the polarizer