Waves

Question 1

whats a progressive wave

Answer 1

carries energy from one place to another without transferring any material

Question 2

Whats a transverse wave and give examples

Answer 2

are those in which the direction of vibration of the particles is perpendicular to the direction in which the wave travels. Examples could be electromagnetic waves, secondary seismic waves, waves on a string or wire

Question 3

Whats a longitudinal wave and give examples

Answer 3

are those in which the direction of vibration of the particles is parallel to the direction in which the wave travels. Examples of this are: sound waves, seismic waves, waves on a slinky.

Question 4

whats an electromagnetic wave

Answer 4

are oscillations of the electric and magnetic fields that progress through space without the need for a substance. The oscillating electric field generates an oscillating magnetic field which generates an electric field and so on. Eg radio,micro, infared, visible, uv, xray and gamma

Question 5

What is frequency

Answer 5

number of waves passing a point every second

Question 6

whats amplitude

Answer 6

it is the maximum displacement of a particle. For a transverse wave, this is the height of a wave crest or the depth of a wave trough from its equilibrium position

Question 7

whats wavelength

Answer 7

is the least distance between two adjacent vibrating particles with the same displacement and velocity at the same time (distance between adjacent crests)

Question 8

whats a cycle and whats a period

Answer 8

-one complete cycle of a wave is from maximum displacement to the next maximum displacement (from one peak to the next).
-it is the time for one complete wave to pass a fixed point

Question 9

formula for wave speed

Answer 9

frequency x wavelength

Question 10

whats polorisation

Answer 10

Polarisation of light only occurs in transverse waves, this is when vibrations of the wave only stay in one plane only, those waves are plane-polarised. The vibrations can change from one plane to another, in this case we call them unpolarised.

Question 11

What is phase difference

Answer 11

between 2 vibrating particles at the same frequency and it is the fraction of a cycle between the vibration of the particles.
1 cycle = 360 degrees = 2 PI radians

Question 12

Explain superposition

Answer 12

combination of waves is superpostion
the principle of superpostion states when 2 waves meet the total displacement at a point is equal to the sum of the individuals displacements at that point.

Question 13

what are Stationary waves

Answer 13

when 2 progressive waves of the same fequency and amplitude pass through each other they combine at fixed points creating nodes and antinodes

Question 14

whats a
-node
-antinode

Answer 14

Node is a point along a standing wave it has min amplitude and has no vibration
antinode are the points where amplitude is at its highest

Question 15

constructive interference

Answer 15

2 waves combine to produce a wave thats bigger then the original wave

Question 16

destructive interfernce

Answer 16

when 2 waves come together and completely cancel each other out